ISSN: 0256-307X 中国物理快报 Chinese Physics Letters

Volume 32 Number 8 August 2015 A Series Journal of the Chinese Physical Society Distributed by IOP Publishing Online: http://iopscience.iop.org/0256-307X http://cpl.iphy.ac.cn

C HINESE P HYSICAL S OCIET Y

CHIN. PHYS. LETT. Vol. 32, No. 8 (2015) 080303 Analysis of Faraday Mirror in Auto-Compensating Quantum Key Distribution *

WEI Ke-Jin(韦克金), MA Hai-Qiang(马海强)**, LI Rui-Xue(李瑞雪), ZHU Wu(朱武), LIU Hong-Wei(刘宏伟), ZHANG Yong(张勇), JIAO Rong-Zhen(焦荣珍) School of Science and State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications, Beijing 100876

(Received 24 April 2015) The ‘plug & play’ quantum key distribution system is the most stable and the earliest commercial system in the quantum communication field. Jones matrix and Jones calculus are widely used in the analysis of this systemand the improved version, which is called the auto-compensating quantum key distribution system. Unfortunately, existing analysis has two drawbacks: only the auto-compensating process is analyzed and existing systems do not fully consider laser phase affected by a Faraday mirror (FM). In this work, we present a detailed analysis of the output of light pulse transmitting in a plug & play quantum key distribution system that contains only an FM, by Jones calculus. A similar analysis is made to a home-made auto-compensating system which contains two FMs to compensate for environmental effects. More importantly, we show that theoretical and experimental results are different in the plug & play interferometric setup due to the fact that a conventional Jones matrixof FM neglected an additional phase 휋 on alternative polarization direction. To resolve the above problem, we give a new Jones matrix of an FM according to the coordinate rotation. This new Jones matrix not only resolves the above contradiction in the plug & play interferometric setup, but also is suitable for the previous analyses about auto-compensating quantum key distribution. PACS: 03.67.Dd, 03.67.Hk DOI: 10.1088/0256-307X/32/8/080303

Quantum key distribution (QKD), known as the crucial component in AC QKD. Its Jones matrix is most promising field to real world applications among widely used in theoretical analyses of AC QKD sys- various quantum information technologies, allows two tems. For the analysis, the main stream is describing distant parties (commonly named Alice and Bob) to the fact, which is first presented by Martinelli[12] that generate a string of unconditional secret key guar- a light, after propagating through an optical fiber and anteed by the law of quantum physics.[1] Since Ben- being reflected by FM, returns orthogonally polarized nett and Brassard presented the first QKD protocol in with a total round-trip phase which is independent of 1984, researchers have implemented many QKD sys- the initial polarization state.[13] Unfortunately, exist- tems, with entangled source, single photon, and con- ing analyses have two drawbacks. First, most of them tinuous source, via free space and optical fiber.[2−8] just followed the main stream and analyzed the com- Generally, the polarization of optical pulses is used pensating process. However, none of them showed ex- for free space QKD, and the phase is known to be the plicitly the output after the light transmits in an AC most promising encoding resource in optical fibers, QKD system, especially, when the system contains the thanking the robustness during transmission. The odd number of FMs.[14−16] Secondly, most of them cite phase encoding QKD system is usually based on the a conventional Jones matrix of FM, as Eq. (6), with- double Mach–Zehnder interferometer, one side in Al- out tracing to its source and its affect to the output in ice and the other in Bob. To make the interferom- AC QKD. Thus existing analyses do not fully consider eter identical and stable, an auxiliary compensating light phase affected by FMs. Recently, some works system is required. However, it is extra costs and based on AC QKD systems have been reported.[17,18] complex.[9,10] A simple, while novel, plug & play QKD In this Letter, we present a detailed analysis of the prototype, proposed by Muller et al.,[11] provides an output after a light pulse transmits through the setup inexpensive and efficient way to solve this problem. in Fig. 1, which is the earliest commercial and most Figure1 shows the setup of a plug & play QKD famous scheme in the AC QKD that contains only an system, pulse transmits through a single mode fiber FM. A similar analysis is carried out to a home-made (SMF) which serves as a quantum channel from Bob to AC scheme which contains two FMs to compensate Alice. Then it is back from Alice to Bob after reflected for the environmental effects. These works can be re- by a Faraday mirror (FM). Since the pulse passes garded as a general Jones matrix analysis for the AC through the same channel twice in reverse order, en- QKD system. More importantly, we show that the vironmental effects during the transmissions, such as conventional Jones matrix of the FM neglects an ad- birefringence in fiber, are auto-compensated. Subse- ditional phase 휋 on alternative polarization direction. quently, many developed QKD systems have used this As a result, theoretical and experimental results are compensating way to deal with environmental effects different in the plug & play QKD setup (or Fig. 1). during transmission. We usually call this type of sys- To solve the gap between experiment and theory, we tems the auto-compensating (AC) QKD. An FM is a present a new Jones matrix of the FM. Thus it resolves

*Supported by the National Natural Science Foundation of China under Grant No 61178010, the Fund of State Key Laboratory of Information Photonics and Optical Communications of Beijing University of Posts and Telecommunications under Grant No 201318, and the Fundamental Research Funds for the Central Universities of China under Grant No 2014TS01. **Corresponding author. Email: [email protected] © 2015 Chinese Physical Society and IOP Publishing Ltd 080303-1 CHIN. PHYS. LETT. Vol. 32, No. 8 (2015) 080303 the problem that theoretical and experimental results a delay line in the lower arm. This does not have any out are different in the mentioned one-FM system orthe effect on the results. Thus the output ofPBS 퐸5 is two-FM system. Furthermore, it is also suitable for (︂ out )︂ the previous analyses. out 퐸2 퐸5 = out . (4) 퐸3 PBS Cir The entire system’s Jones matrix (for the forward and Ein Eout Eout 1 C 2 T 1 5 FM backward propagations through SMF) is thus given by Eout QC 3 Ein Ein LD 2 R 5 PMA Eout Eout 푇total = exp{푖휃}퐹old, (5) 4 3 D1 Ein DL PMB 3 where 휃 is the propagation phase, and the Jones ma- D2 Alice Bob trix of the FM 퐹old is Fig. 1. The plug & play interferometric setup. LD: laser (︂ 0 −1 )︂ 퐹 = . (6) diode, Cir: circulator, C: a 50/50 coupler, C: PBS: polar- old −1 0 ization beam splitter, FM: Faraday mirror, PMA, PMB: phase modulators, D1, D2: single photon detectors, QC: quantum channel. Furthermore, 퐹old is a conventional formula which is widely cited in the previous works about the AC Figure1 shows a plug & play interferometric setup, QKD.[14,15,19] widely used in QKD over SMF. In detail, a laser pulse After the light is reflected by the FM, the input of is sent by a laser diode (LD) and passes through a in the PBS 퐸1 is circulator (Cir) to a 50/50 coupler (C) that splits it in out into two pulses propagating through an upper arm 퐸5 = 푇total · 퐸5 . (7) and a lower arm (that includes a delay line) with the According to the principle of PBS, the coupler’s inputs same polarization, respectively. The pulses arrive at in in a polarization beam splitter (PBS) and leave the Bob 퐸2 and 퐸3 can be described by station by the same polarization beam splitters PBS (︂ 1 0 )︂ port 1: the lower arm pulse is vertically polarized and 퐸in = 퐸in, (8) 2 0 0 5 the upper one is horizontally polarized. Then, the up- per arm and the lower arm pulses are transmitted over (︂ 0 1 )︂ 퐸in = 퐸in. (9) SMF and reflected at the FM, which rotates their po- 3 0 0 5 larizations by 90∘, then transmits back. Both pulses out continue their backward propagation over the SMF Finally, the output vectors 퐸1 corresponding to the out and are directed by the PBS to the opposite arms (in measurement result of D1 and 퐸4 corresponding to regards to their forward propagation), thus they ar- the measurement result of D2 are found by the electric rive at the same time at the coupler C, where they field amplitude transmission equation for a symmetri- interfere. Depending on the phase difference 휙 (that cal coupler could be controlled by Alice’s phase modulator PMA √ and Bob’s PM ) between the pulses, they are detected out 2 in in B 퐸1 = (퐸2 + 푖퐸3 ), (10) to either detector D1 or D2 if the phase difference √2 휙 = 0 ± 2n휋, or 휙 = 휋 ± 2푛휋, where 푛 is an inte- 2 퐸out = (푖퐸in + 퐸in). (11) ger; or in both detectors with different probabilities 4 2 2 3 for other 휙 values. Thus the plug & play system is auto-compensated for propagation time difference be- After substituting all formula (already calculated in this section) one can finally obtain the following ex- tween the upper arm and lower arm pulses since they out out travel the same path length. pression for the 퐸1 and 퐸4 For simplicity, the laser pulses are assumed to be (︂ )︂ out 1 퐸푥 initially emitted with horizontal polarization. After 퐸1 = − 푖 exp(푖휃) , (12) out 2 0 being split by the coupler C, the upper pulse 퐸2 out (︂ )︂ and the low pulse 퐸3 are given by out 1 0 퐸4 = − exp(푖휃) , (13) √ 2 0 out 2 in 퐸2 = 퐸1 , (1) which show that this system really compensates for √2 the birefringence of SMF. Moreover, the photons are out 2 in detected by D1 when both users have not modulated 퐸3 = 푖 퐸1 , (2) 2 the phase using conventional Jones Matrix of FM 퐹old in the theoretical analysis. We remark that this de- in where the vector 퐸1 is the output of Cir, tection result in theory is not in conformity with the experimental results, which will be shown in the fol- (︂ 퐸 )︂ 퐸in = 푥 . (3) lowing. 1 0 Reasons of the missing phase are complex. First, many AC QKD systems are based on phase encoding To simplify the analysis, the two pulses are assumed to while polarization detection. This phase does not in- arrive at the PBS simultaneously even though there is fluence the experimental results.[19,20] Secondly, many 080303-2 CHIN. PHYS. LETT. Vol. 32, No. 8 (2015) 080303

AC QKD systems contain two FMs, therefore the to- sion equation for a 50/50 coupler [14,20,21] tally additional phase is 2휋 and the output is √ not affected. In this work, we design an ACQKD 2 퐸out = 퐸in, (15) setup based on two FMs. The experimental results b 2 a from the two-FM system show that, depending on √ out 2 in Jones calculus, the output of the light pulse is similar 퐸c = 푖 퐸a , (16) with the previous one-FM QKD system when the con- 2 ventional Jones matrix of the FM is used. However, where the vector 퐸in is the output of Cir the experimental result is identical to the theoretical a calculation. (︂ 퐸 )︂ The experimental setup is shown in Fig. 2.A 퐸in = 푥 . (17) a 0 pulsed laser emits pulses of photons, for conveniently denoted, in a horizontal polarization state. Then After the two pulses passed through the two PBSs and pulses pass through a circulator Cir and an ordinary the two FMs, the vector 퐸in and 퐸in are given by 50/50 coupler C before entering two PBS in the loop b c of a Sagnac type interferometer. A photon pulse, af- in out ter traveling in the clockwise direction in the upper 퐸b = 퐽total · 퐸c , (18) in out arm through PBS1 and traversing the quantum chan- 퐸c = 퐽total · 퐸a . (19) nel QC, is phase modulated by Bob, reflected by FM ∘ FMB with a 90 polarization rotation, and returns to When the interference occurs at C, the result is ex- be reflected at PBS1 and PBS2. After phase modula- pressed as tion by Alice’s modulator PM1 and reflection at her √ FMA it passes through PBS2 to exit the interferom- 2 1 (︂ 퐸 )︂ eter at C. The pulse traveling anti-clockwise in the 퐸out = (퐸in + 푖퐸in) = − 푖 exp(푖휃) 푥 , (20) a 2 b c 2 0 lower arm travels exactly the same path while in the √ opposite direction, thus interference occurs at C, and 2 1 (︂ 0 )︂ 퐸out = (푖퐸in + 퐸in) = − exp(푖휃) . (21) a photon is detected at either D1 or D2 depending on d 2 b c 2 0 the phases of PMA and PMB. Comparing Eqs. (12), (13), (20) and (21), the theoret- Cir PBS1 ical results of these setups are identical, although the Ein Eout a b C FM number of FM is different in the setups. However, in Ein QC A Eout b LD a the following we show that the experimental results of PMA out out these setups are significantly different. Furthermore, Ed Ec Alice D1 Ein since most AC QKD systems are the similar model c PM PBS2 B [3,15,22] FMB Bob D2 in this work, these works can be regard as a general Jones matrix analysis for AC QKD systems. Fig. 2. Two-FM QKD setup. LD: laser diode, Cir: cir- culator, C: a 50/50 coupler C, PBS1, PBS2: polarization Visibility=96.6% beam splitters, FMA, FMB: Faraday mirrors, PMA, PMB: 8000 D1 phase modulators, D1, D2: single photon detectors, QC: 7000 D2 quantum channel. 6000

The two PBSs are just used to reflect the light to (s) 5000 the opposite directions, and do not influence the phase 4000

of the light. Cou nts According to Eq. (5) and the Jones calculus, the 3000 overall Jones matrix of two FMs 퐽total in this system 2000 is described by 1000

0 0 2 4 6 8 10 퐽total = 퐹old푇total PMA (V) (︂ 0 −1 )︂ (︂ 0 −1 )︂ = exp {푖휃} Fig. 3. Counts of D1, D2 versus the modulation voltage −1 0 −1 0 of PMA in the plug & play QKD setup. (︂ 1 0 )︂ Both setups are performed by using the same type = exp {푖휃} , (14) 0 1 of optical components. The voltage 푉PMA of Alice’s phase modulator is changed while the voltage of Bob’s modulator is fixed at 0 in the experimental test. Fig- out which shows that the upper vector 퐸a and the lower ures3 and 4 show the count rates in D1 and D2 in out vector 퐸b are directed to the opposite arms with a the plug & play QKD setup and in the two-FM QKD propagation phase 휃. setup, respectively. In a similar analysis to the one mentioned above, We can see that when the voltage of PMA is 0 out out the upper pulse 퐸b and the lower pulse 퐸c are in both setups, the D2 is clicked in the plug & play found by using the electric field amplitude transmis- interferometric setup, which is the exact opposite of 080303-3 CHIN. PHYS. LETT. Vol. 32, No. 8 (2015) 080303 the theoretical result mentioned above. On the con- An FM is a combination of a 45∘ Faraday rotator FR trary, D1 is clicked in the two-FM QKD setup, which is and a normal plane mirror M. The first step toward identical with the theoretical result mentioned above. this objective of Jones matrix is the definition of the Furthermore, the modulation curves of two setups are reference system. The conventions used to define the just the opposite. state of polarization of the light and the orientations of the polarization-active devices. Here we adopt a Visibility=96.9% right-handed Cartesian coordinate system. The C1 D1 8000 with blue color represents the coordinates of forward D2 propagation, the coordinates of backward propagation C2 is green color.[23] 6000

(s) x 45O 4000 z M x 45O y Cou nts y 2000 FR z C2

0 0 2 4 6 8 10 x 90O PMA (V) y x z Fig. 4. Counts of D1, D2 versus the modulation voltage E z of PMA in the two-FM QKD setup. y Consequently, there is an additional phase 휋 that C1 makes the results different in theory and experiment Fig. 5. Schematic diagram of FM. C1: the coordinates in the one-FM setup. Re-observing the schematic dia- of forward propagation, C2: the coordinates of backward ∘ gram of Fig.1, intuitively, we conclude that the FM is propagation, FR: 45 Faraday rotator, M: plane mirror, only possible to affect the result of interference since blue dashed line: FR rotation direction. both pulses transmit the PBS or couple C twice with For non-reciprocal components such as Faraday identical polarization, although the directions may be rotators, reversing the propagation direction also different. For example, the upper pulse passes through changes the sign of the Faraday rotation angle. the PBS with horizontal polarization in the forward Thus the forward and backward polarization trans- propagation and reflect from the input 1 to the output formations through a Faraday rotator are related by 퐹 퐹 푅 in the backward propagation, and the propagation 푅b (푂) = 푅f (−푂), where of the lower pulse is similar, which is reflected by the (︂ cos 휃 sin 휃 )︂ PBS from 푅 to 1 and transmits directly from 1 to 푇 . 푅퐹 (휃) = . (22) − sin 휃 cos 휃 Moreover, the structure of an FM is a Faraday rota- tor connecting to a plane mirror. According to the The Jones matrix of a mirror is also expressed as Fresnel formulas, a plane mirror takes half-wave loss (︂ 1 0 )︂ according to the polarization of the light reflected by 푀 = . (23) it, i.e., there is an additional phase 휋 when the light 0 −1 is vertical and there is no phase shift when the light Therefore, the Jones matrix of an FM is described as is horizontal. In the plug & play setup, the upper (︂ )︂ pulse enters into the FM with horizontal polarization, 퐹 ∘ −1 0 퐹 ∘ 퐹old = 푅 (−45 ) · · 푅 (+45 ) however the lower pulse enters into it with the ver- 0 1 tical polarization. As mentioned above. Part of the (︂ 1 −1 )︂ (︂ −1 0 )︂ (︂ 1 1 )︂ = previous AC QKD systems are based on the polar- 1 1 0 1 −1 1 ization detection, although parts are based on inter- (︂ 0 −1 )︂ ference detection, they have odd FM in their system. = , (24) Consequently, the additional phase 휋 influenced by an −1 0 FM is neglected in these works. which is the format of Jones matrix of an FM most The conventional Jones matrix of FM, without widely cited by previous studies. We can easily find considering polarization-dependent half-loss in an FM, that the input light and the output light is not orthog- causes the difference between experiment and theory, onality when we define the Jones matrix of an FMas i.e., it does not consider that there is a half-wave loss Eq. (24), i.e., if we denote the Jones vector of the input when a light with horizontal polarization is reflected light as by an FM. On the contrary, there is no half-wave (︂ )︂ loss for vertical polarization light. Next, we show a cos 휃 퐸 = . (25) specified derivation of the Jones matrix of anFM. sin 휃 Then by revising the coordinate system, we present That of the output light becomes a new Jones matrix which imports the polarization- independent half-wave loss in an FM. (︂ − sin 휃 )︂ 퐸′ = 퐹 · 퐸 = . (26) The schematic diagram of an FM is shown in Fig. 5. old − cos 휃 080303-4 CHIN. PHYS. LETT. Vol. 32, No. 8 (2015) 080303

It easily infers that 퐸′ · 퐸 ̸= 0, which is an error indi- interferometric setup. Moreover, we design a two-FM cation for the property of an FM. interferometric setup, demonstrating that the FM in- With the Jones matrix, it is convenient to research duces an additional phase 휋 when the polarization of the transformations of polarized light in an optical cir- light is vertical. To resolve this problem, we give a cuit. Originally, there is an implicit assumption that new Jones matrix of the FM according to the coordi- the direction of propagation of the light pulse is fixed. nate rotation. We remark that although the conven- However, in the simplest optical circuits this condi- tional Jones matrix of an FM does not give erroneous tion is seldom fulfilled due to reflections from mirrors result in previous work, an accurate Jones matrix is or other optical surfaces. Jones himself made ma- necessary, since the Jones matrix of an FM is more trix transformation rules to deal with this problem in widely for the analysis of QKD system containing an which the direction of light was reversed, while these FM, not only in AC QKD, but also other QKD fields rules depend on the reference system used to the de- such as attack strategy[22] and security QKD system scription of the optical circuit, i.e., when a reference design.[24] We cannot foresee the problem if the con- system is chosen, not only the matrix transformation ventional Jones matrix of an FM is still used, while rules but also the form of particular matrices must be we have proven the error in the plug & play QKD sys- consistent with it; otherwise the Jones calculus gives tem. We wish our work can recall related researchers’ erroneous results. Re-observing the schematic dia- attention. gram in Fig. 5, the previous format of Jones matrix of Wu Ling-An is gratefully acknowledged for help- an FM is the case that the coordinate system is mov- ful discussion. Thank Tang Zhi-Yuan for revising this ing with the propagation of light, thus in the reference manuscript. system the forward coordinates C1 are different from the backward coordinates C2, which depends on the right-handed Cartesian coordinate system. This case References violates the rules proposed by Jones. To satisfy the orthogonality of the forward and backward light and [1] Scarani V, Bechmann-Pasquinucci H, Cerf N J, Dusek M, Lutkenhaus N and Peev M 2009 Rev. Mod. Phys. 81 1301 also to revise the neglecting of half-wave loss, our so- [2] Buttler T W, Hughes J R, Kwiat G P, Lamoreaux K S, lution is simply fixing the coordinate system, by using Luther G G, Morgan L G, Nordholt E J, Peterson G C and the transformation matrix of the coordinate rotation. Simmons M C 1998 Phys. Rev. Lett. 81 3283 The revised Jones matrix of an FM 퐹 is indicated [3] Stucki D, Gisin N, Guinnard O, Ribordy G and Zbinden H new 2002 New J. Phys. 4 41 as [4] Mo X F, Zhu B, Han Z F, Gui Y Z and Gun G C 2005 Opt. Lett. 30 2632 (︂ 1 0 )︂ (︂ 0 −1 )︂ [5] Yin Z Q, Han Z F, Chen W, Xu F X, Wu Q L and Guo G 퐹 = · 퐹 = . (27) new 0 −1 old 1 0 C 2008 Chin. Phys. Lett. 25 3547 [6] Zhu Z C and Zhang Y Q 2010 Chin. Phys. Lett. 27 060303 [7] Stucki D, Walenta N, Vannel F, Thew R T, Gisin N, Let us consider the theoretical analysis again. At this Zbinden H, Gray S, Towery C R and Ten S 2009 New J. time, Eq. (5) is expressed as Phys. 11 075003 [8] Ma H Q, Wei K J and Yang J H 2013 J. Opt. Soc. Am. B (︂ )︂ 30 2560 0 −1 [9] Marand C and Townsend P D 1995 Opt. Lett. 20 1695 푇total = exp{푖휃}퐹new = exp{푖휃} . (28) 1 0 [10] Gobby C, Yuan Z L and Shields A J 2004 Appl. Phys. Lett. 84 3762 Using the similar calculation as detailed above, the [11] Muller A, Herzog T, Huttner B, Tittel W, Zbinden H and Gisin N 1997 Appl. Phys. Lett. 70 793 output of the system is written as [12] Martinelli M 1989 Opt. Commun. 72 341 √ [13] Bogdanski J, Rafiei N and Bourennane M 2008 Phys. Rev. (︂ )︂ A 78 062307 out 2 in in 1 0 퐸1 = (퐸b + 푖퐸c ) = exp(푖휃) , (29) [14] Sun S H, Ma H Q, Han J J, Liang L M and Li C Z 2010 2 2 0 Opt. Lett. 35 1203 √ [15] Liu Y, Ju L, Liang X L, Tang S B, Tu G L S, Zhou L, Peng 2 1 (︂ 퐸 )︂ 퐸out = (푖퐸in + 퐸in) = exp(푖휃) 푥 , (30) C Z, Chen K, Chen T Y, Chen Z B and Pan J W 2012 Phys. 4 2 b c 2 0 Rev. Lett. 109 030501 [16] Ma H Q, Wei K J and Yang J H 2013 Opt. Lett. 38 4494 which are identical to the experimental result shown [17] Xu F H, Wei K J, Sajeed S, Kaiser S, Sun S H, Tang Z Y, Qian L, Makarov V and Lo H K 2015 arXiv:1408.3667 in Fig.3. [quant-ph] In summary, we have presented a detailed analy- [18] Xu F H, Arrazola J M, Wei K J, Wang W Y, Palacios-Avila sis of the output of light pulse transmitting in one- P, Feng C, Sajeed S and Lo H K 2015 arXiv:1503.05499 FM and two-FM AC QKD systems by Jones calculus. [quant-ph] [19] Bethune D S and Risk W P 2002 New J. Phys. 4 42 Our work can be regarded as a general analysis for [20] Cho S B and Noh T G 2009 Opt. Express 17 19027 the AC QKD system since most AC QKD systems [21] Ma H Q, Zhao J L and Wu L A 2007 Opt. Lett. 32 698 are of the similar model. More importantly, we have [22] Sun S H, Jiang M S and Liang L M 2011 Phys. Rev. A 83 shown that by the conventional Jones matrix of an 062331 [23] Pistoni N C 1995 Appl. Opt. 34 7870 FM, the theoretical results are different from the ex- [24] Tang Z Y, Liao Z F, Xu F H, Qi B, Qian L and Lo H K perimental results in a plug & play auto compensating 2014 Phys. Rev. Lett. 112 190503

080303-5 Chinese Physics Letters Volume 32 Number 8 August 2015

GENERAL 080301 The Security Analysis of Two-Step Quantum Direct Communication Protocol in Collective-Rotation Noise Channel LI Jian, SUN Feng-Qi, PAN Ze-Shi, NIE Jin-Rui, CHEN Yan-Hua, YUAN Kai-Guo 080302 Phase-Coding Self-Testing Quantum Random Number Generator SONG Xiao-Tian, LI Hong-Wei, YIN Zhen-Qiang, LIANG Wen-Ye, ZHANG Chun-Mei, HAN Yun-Guang, CHEN Wei, HAN Zheng-Fu 080303 Analysis of Faraday Mirror in Auto-Compensating Quantum Key Distribution WEI Ke-Jin, MA Hai-Qiang, LI Rui-Xue, ZHU Wu, LIU Hong-Wei, ZHANG Yong, JIAO Rong-Zhen 080304 Quantum Interference by Entangled Trajectories XU Feng, WANG Li-Fei, CUI Xiao-Dong 080305 Effect of Quantum Coins on Two-Particle Quantum Walks GAN Shu, HE Xing-Dao, LIU Bin, FENG Cui-Di 080306 A Novel Basis Splitting Eavesdropping Scheme in Quantum Cryptography Based on the BB84 Protocol ZHAO Nan, ZHU Chang-Hua, QUAN Dong-Xiao 080401 Time-Like Geodesic Motion in Schwarzschild Spacetime with Weak-Field Limit ZHANG Ruan-Jing, CHEN Ju-Hua, GAN Qiao-Shan, WANG Yong-Jiu 080501 High-Fidelity Hugoniots of α Phase RDX Solid from High-Quality Force Field with Thermal, Zero-Point Vibration, and Anharmonic Effects SONG Hua-Jie, LI Hua, HUANG Feng-Lei, ZHANG Shuo-Dao, HONG Tao 080701 The Improved Design of Multi-channel Thin Gap Chamber Simulation Signal Source for the ATLAS Detector Upgrade HU Kun, LU Hou-Bing, WANG Xu, , HAN Liang, JIN Ge

THE PHYSICS OF ELEMENTARY PARTICLES AND FIELDS 081101 Dyson–Schwinger Equations of Chiral Chemical Potential TIAN Ya-Lan, CUI Zhu-Fang, WANG Bin, SHI Yuan-Mei, YANG You-Chang, ZONG Hong-Shi

081201 Production of High-pT Kaon and Pion in pp and Au–Au Collisions by Resolved Photoproduction Processes -Bing, YANG Hai-Tao, LI Yun-De

ATOMIC AND MOLECULAR PHYSICS 083101 Static Dipole Polarizabilities for Low-Lying Rovibrational States of HD+ TIAN Quan-Long, TANG Li-Yan, YAN Zong-Chao, SHI Ting-Yun 083102 Stereodynamics Study of Li+HF→LiF+H Reactions on X2A0 Potential Energy Surface at Collision Energies below 5.00 kcal/mol LI Hong-Zheng, LIU Xin-Guo, TAN Rui-Shan, HU Mei 083201 Experimental Scheme of 633 nm and 1359 nm Good-Bad Cavity Dual-Wavelength Active Optical Frequency Standard -Chao, PAN Duo, ZHUANG Wei, CHEN Jing-Biao 083401 Laser Polarization Orientations in (e, 2e) Reactions in Atoms Ajana I., Makhoute A., Khalil D. 083601 Triplet Exciton Transition Induced Highly Efficient Fluorescent Channel in Organic Electroluminescence CHEN Ren-Ai, SUN Xin 083701 Preparation of Ultracold Li+ Ions by Sympathetic Cooling in a Linear Paul Trap CHEN Ting, DU Li-Jun, SONG Hong-Fang, LIU Pei-Liang, HUANG Yao, TONG Xin, GUAN Hua, GAO Ke-Lin FUNDAMENTAL AREAS OF PHENOMENOLOGY(INCLUDING APPLICATIONS) 084201 Tunable, High-Order Harmonically Mode-Locked All-Normal-Dispersion Ytterbium Fiber Laser LV Zhi-Guo, TENG Hao, WANG Li-Na, WANG Rui, WEI Zhi-Yi 084202 Quaternion Approach to Solve Coupled Nonlinear Schr¨odingerEquation and Crosstalk of Quarter-Phase-Shift-Key Signals in Polarization Multiplexing Systems LIU Lan-Lan, WU Chong-Qing, SHANG Chao, WANG Jian, GAO Kai-Qiang 084203 Optimization of 1.3-µm InGaAsP/InP Electro-Absorption Modulator WANG Hui-Tao, ZHOU Dai-Bing, ZHANG Rui-Kang, LU Dan, ZHAO Ling-Juan, ZHU Hong-Liang, WANG Wei, JI Chen 084204 A Mid-IR Optical Parametric Oscillator Pumped by an Actively Q-Switched Ho:YAG Ceramic Laser YUAN Jin-He, DUAN Xiao-Ming, YAO Bao-Quan, LI Jiang, SHEN Ying-Jie, CUI Zheng, DAI Tong-Yu, PAN Yu-Bai 084205 Experimental Study on a Passively Q-Switched Ho:YLF Laser with Polycrystalline Cr2+:ZnS as a Saturable Absorber CUI Zheng, YAO Bao-Quan, DUAN Xiao-Ming, LI Jiang, BAI Shuang, LI Xiao-Lei, ZHANG Ye, YUAN Jin-He, DAI Tong-Yu, JU You-Lun, LI Chao-Yu, PAN Yu-Bai 084301 High-Frequency Guided Wave Scattering by a Partly Through-Thickness Hole Based on 3D Theory ZHANG Hai-Yan, XU Jian, MA Shi-Wei 084601 Numerical Simulation of Two Different Flexible Bodies Immersed in Moving Flow WANG Si-Ying, HUANG Ming-Hai, YIN Xie-Zhen

PHYSICS OF GASES, PLASMAS, AND ELECTRIC DISCHARGES 085201 Diagnostics of Metal Plasma in Radio Frequency Glow Discharge during Electron Beam Evaporation YU Yong-Hao, -Ping, WANG Xiao-Feng, JIANG Wei, CHEN Qiong 085202 The Impact of Beam Deposition on Bootstrap Current of Fast Ion Produced by Neutral Beam Tangential Injection HUANG Qian-Hong, GONG Xue-Yu, LU Xing-Qiang, YU Jun, CAO Jin-Jia 085203 Positron-Acoustic Shock Waves in a Degenerate Multi-Component Plasma Shah M. G., Hossen M. R., Sultana S., Mamun A. A.

CONDENSED MATTER: STRUCTURE, MECHANICAL AND THERMAL PROPERTIES 086201 Properties of Liquid Nickel along Melting Lines under High Pressure CAO Qi-Long, WANG Pan-Pan, HUANG Duo-Hui, YANG Jun-Sheng, WAN Ming-Jie, WANG Fan-Hou 086801 Thermal Conductance of Cu and Carbon Nanotube Interface Enhanced by a Graphene Layer HUANG Zheng-Xing, WANG Li-Ying, BAI Su-Yuan, TANG Zhen-An 086802 Surface Acoustic Wave Humidity Sensors Based on (1120)¯ ZnO Piezoelectric Films Sputtered on R-Sapphire Substrates WANG Yan, ZHANG Shu-Yi, FAN Li, SHUI Xiu-Ji, YANG Yue-Tao

CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES

087101 Anisotropic Transport and Magnetic Properties of Charge-Density-Wave Materials RSeTe2 (R = La, Ce, Pr, Nd) WANG Pei-Pei, LONG Yu-Jia, ZHAO Ling-Xiao, CHEN Dong, XUE Mian-Qi, CHEN Gen-Fu 087102 Ti/Al Based Ohmic Contact to As-Grown N-Polar GaN FENG Zhi-Hong, WANG Xian-Bin, WANG Li, LV Yuan-Jie, FANG Yu-Long, DUN Shao-Bo, ZHAO Zheng-Ping 087103 Effects of N on Electronic and Mechanical Properties of H-Type SiC LIU Yun-Fang, CHENG Lai-Fei, ZENG Qing-Feng, ZHANG Li-Tong 087201 Thermal Analysis of Organic Light Emitting Diodes Based on Basic Heat Transfer Theory ZHANG Wen-Wen, WU Zhao-Xin, LIU Ying-Wen, DONG Jun, YAN Xue-Wen, HOU Xun

087401 Growth of High-Quality Superconducting FeSe0.5Te0.5 Thin Films Suitable for Angle-Resolved Photoemission Spectroscopy Measurements via Pulsed Laser Deposition KONG Wan-Dong, LIU Zhi-Guo, WU Shang-Fei, WANG Gang, QIAN Tian, YIN Jia-Xin, RICHARD Pierre, YAN Lei, DING Hong 0 087501 Structure and Magnetic Properties of the γ -Fe4N Films on Cu Underlayers JIANG Feng-Xian, ZHAO Ye, ZHOU Guo-Wei, ZHANG Jun, FAN Jiu-Ping, XU Xiao-Hong 087502 RC-Circuit-Like Dynamic Characteristic of the Magnetic Domain Wall in Flat Ferromagnetic Nanowires CHEN Cheng, PIAO Hong-Guang, SHIM Je-Ho, PAN Li-Qing, KIM Dong-Hyun

087503 Ferroelectricity in the Ferrimagnetic Phase of Fe1−xMnxV2O4 ZHAO Ke-Han, WANG Yu-Hang, SHI Xiao-Lan, LIU Na, ZHANG Liu-Wan 087504 Large Tunability of Physical Properties of Manganite Thin Films by Epitaxial Strain WEI Wen-Gang, WANG Hui, ZHANG Kai, LIU Hao, KOU Yun-Fang, CHEN Jin-Jie, DU Kai, ZHU Yin-Yan, HOU Deng-Lu, WU Ru-Qian, -Feng, SHEN Jian

CROSS-DISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY 088101 Defect Reduction in GaAs/Si Films with the a-Si Buffer Layer Grown by Metalorganic Chemical Vapor Deposition , HU Hai-Yang, HE Yun-Rui, DENG Can, WANG Qi, DUAN Xiao-Feng, HUANG Yong-Qing, REN Xiao-Min 088102 Preparation of Ta-Doped TiO2 Using Ta2O5 as the Doping Source XU Cheng, LIN Di, NIU Ji-Nan, QIANG Ying-Huai, LI Da-Wei, TAO Chun-Xian 088103 Growth of a-Plane GaN Films on r-Plane Sapphire by Combining Metal Organic Vapor Phase Epitaxy with the Hydride Vapor Phase Epitaxy JIANG Teng, XU Sheng-Rui, ZHANG Jin-Cheng, LIN Zhi-Yu, JIANG Ren-Yuan, HAO Yue 088104 Nano-Crystalline Diamond Films Grown by Radio-Frequency Inductively Coupled Plasma Jet Enhanced Chemical Vapor Deposition SHI Yan-Chao, LI Jia-Jun, LIU Hao, ZUO Yong-Gang, BAI Yang, SUN Zhan-Feng, MA Dian-Li, CHEN Guang-Chao 088301 Effect of Abrasive Concentration on Chemical Mechanical Polishing of Sapphire YAN Wei-Xia, ZHANG Ze-Fang, GUO Xiao-Hui, LIU Wei-Li, SONG Zhi-Tang

088401 InxGa1−xN/GaN Multiple Quantum Well Solar Cells with Conversion Efficiency of 3.77% LIU Shi-Ming, XIAO Hong-Ling, WANG Quan, YAN Jun-Da, ZHAN Xiang-Mi, GONG Jia-Min, WANG Xiao-Liang, WANG Zhan-Guo 088501 Impact of Band-Engineering to Performance of High-k Multilayer Based Charge Trapping Memory LIU Li-Fang, PAN Li-Yang, ZHANG Zhi-Gang, XU Jun 088502 Anomalous Channel Length Dependence of Hot-Carrier-Induced Saturation Drain Current Degradation in n-Type MOSFETs ZHANG Chun-Wei, LIU Si-Yang, SUN Wei-Feng, ZHOU Lei-Lei, ZHANG Yi, SU Wei, ZHANG Ai-Jun, LIU Yu-Wei, HU Jiu-Li, HE Xiao-Wei 088503 Discrimination Voltage and Overdrive Bias Dependent Performance Evaluation of Passively Quenched SiC Single-Photon-Counting Avalanche Photodiodes LIU Fei, YANG Sen, ZHOU Dong, LU Hai, ZHANG Rong, ZHENG You-Dou

088504 High Responsivity Organic Ultraviolet Photodetector Based on NPB Donor and C60 Acceptor WANG Yong-Fan, QU Feng-Dong, ZHOU Jing-Ran, GUO Wen-Bin, DONG Wei, LIU Cai-Xia, RUAN Sheng-Ping 088505 Laser-Induced Single Event Transients in Local Oxidation of Silicon and Deep Trench Isolation Silicon-Germanium Heterojunction Bipolar Transistors LI Pei, GUO Hong-Xia, GUO Qi, ZHANG Jin-Xin, WEI Ying, 088506 Temperature-Dependent Drain Current Characteristics and Low Frequency Noises in Indium Zinc Oxide Thin Film Transistors LIU Yuan, WU Wei-Jing, QIANG Lei, WANG Lei, EN Yun-Fei, LI Bin 088701 Motion-Enhanced Quantum Entanglement in the Dynamics of Excitation Transfer SONG Wei, HUANG Yi-Sheng, YANG Ming, CAO Zhuo-Liang 088801 Effect of Valence Band Tail Width on the Open Circuit Voltage of P3HT:PCBM Bulk Heterojunction Solar Cell: AMPS-1D Simulation Study Bushra Mohamed Omer 088901 Exact Solution for Clustering Coefficient of Random Apollonian Networks FANG Pin-Jie, ZHANG Duan-Ming, HE Min-Hua, JIANG Xiao-Qin