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Putting Mechanics into Quantum Mechanics Nanoelectromechanical structures are starting to approach the ultimate quantum mechanical limits for detecting and exciting motion at the nanoscale. Nonclassical states of a mechanical resonator are also on the horizon. Keith C. Schwab and Michael L. Roukes verything moves! In a world dominated by electronic achieved to read out those devices, now bring us to the Edevices and instruments it is easy to forget that all realm of quantum mechanical systems. measurements involve motion, whether it be the motion of electrons through a transistor, Cooper pairs or quasiparti- The quantum realm cles through a superconducting quantum interference de- What conditions are required to observe the quantum prop- vice (SQUID), photons through an optical interferome- erties of a mechanical structure, and what can we learn ter—or the simple displacement of a mechanical element. when we encounter them? Such questions have received Nanoscience today is driving a resurgence of interest in considerable attention from the community pursuing grav- mechanical devices, which have long been used as front itational-wave detection: For more than 25 years, that com- ends for sensitive force detectors. Among prominent his- munity has understood that the quantum properties of me- torical examples are Coulomb’s mechanical torsion bal- chanical detectors will impose ultimate limits on their force 6,7 ance, which allowed him in 1785 to establish the inverse- sensitivity. Through heroic and sustained efforts, the square force law of electric charges, and Cavendish’s Laser Interferometer Gravitational Wave Observatory mechanical instrument that allowed him in 1798 to meas- (LIGO) with a 10-kg test mass, and cryogenic acoustic de- ure the gravitational force between two lead spheres. -
Nanoelectromechanical Systems Face the Future Michael Roukes
physicsworldarchive.iop.org Nanoelectromechanical systems face the future Michael Roukes From Physics World February 2001 © IOP Publishing Ltd 2007 ISSN: 0953-8585 Institute of Physics Publishing Bristol and Philadelphia Downloaded on Tue Oct 09 05:06:27 BST 2007 [198.11.27.40] FEATURES A host of novel applications and new physics could be unleashed as microelectromechanical systems shrink towards the nanoscale Nanoelectromechanical systems face the future Michael Roukes IN THE late 1950s visionary physicist 1 Feynman's challenge Richard Feynman issued a public chal- lenge by offering $1000 to the first person to create an electrical motor "smaller than 1 /64th of an inch". Much to Feynman's consternation the young man who met this challenge, William McLellan, did so by investing many tedious and painstaking hours building the device by hand using tweezers and a microscope (figure 1). McLellan's motor now sits in a display case at the California Institute of Tech- nology and has long since ceased to spin. Meanwhile, in the field that Feynman hoped to incite, the wheels are turning- (a) Richard Feynman viewing the micromotor built by William McLellan (left) who won the challenge to both figuratively and literally — in many build the first motor smaller than l/64th of an inch, (b) The motor, 3.81 mm wide, photographed under f, university and corporate laboratories, an optical microscope. The huge object above it is the head of a pin. & and even on industrial production lines. Indeed, the field of microelectromechanical systems (MEMS), MEMS at sizes below one micrometre. This stands in stri- which became firmly established in the mid-1980s, has now king contrast to the recent developments in mainstream matured to the point where we can be rather blase about the microelectronics where chips are now mass-produced with mass production of diminutive motors that are hundreds of features as small as 0.18 microns. -
Arxiv:1403.3703V1 [Quant-Ph]
Thermalization properties at mK temperatures of a nanoscale optomechanical resonator with acoustic-bandgap shield Se´anM. Meenehan,1, ∗ Justin D. Cohen,1, ∗ Simon Gr¨oblacher,1, 2, ∗ Jeff T. Hill,1 Amir H. Safavi-Naeini,1 Markus Aspelmeyer,2 and Oskar Painter1, y 1Institute for Quantum Information and Matter and Thomas J. Watson, Sr., Laboratory of Applied Physics, California Institute of Technology, Pasadena, CA 91125, USA 2Vienna Center for Quantum Science and Technology (VCQ), Faculty of Physics, University of Vienna, A-1090 Wien, Austria (Dated: March 18, 2014) Optical measurements of a nanoscale silicon optomechanical crystal cavity with a mechanical reso- nance frequency of 3:6 GHz are performed at sub-kelvin temperatures. We infer optical-absorption- induced heating and damping of the mechanical resonator from measurements of phonon occu- pancy and motional sideband asymmetry. At the lowest probe power and lowest fridge temperature (Tf = 10 mK), the localized mechanical resonance is found to couple at a rate of γi=2π = 400 Hz 6 (Qm = 9 × 10 ) to a thermal bath of temperature Tb ≈ 270 mK. These measurements indicate that silicon optomechanical crystals cooled to millikelvin temperatures should be suitable for a variety of experiments involving coherent coupling between photons and phonons at the single quanta level. acoustic 0.5 Introduction. - The coupling of a mechanical object's a b c − ωm ωm radiation κi 0.4 motion to the electromagnetic field of a high finesse cav- shield 0.3 R ity forms the basis of various precision measurements [1], 0.2 κ = κe+κi from large-scale gravitational wave detection [2] to mi- 0.1 0 croscale accelerometers [3]. -
2018 March Meeting Program Guide
MARCHMEETING2018 LOS ANGELES MARCH 5-9 PROGRAM GUIDE #apsmarch aps.org/meetingapp aps.org/meetings/march Senior Editor: Arup Chakraborty Robert T. Haslam Professor of Chemical Engineering; Professor of Chemistry, Physics, and Institute for Medical Engineering and Science, MIT Now welcoming submissions in the Physics of Living Systems Submit your best work at elifesci.org/physics-living-systems Image: D. Bonazzi (CC BY 2.0) Led by Senior Editor Arup Chakraborty, this dedicated new section of the open-access journal eLife welcomes studies in which experimental, theoretical, and computational approaches rooted in the physical sciences are developed and/or applied to provide deep insights into the collective properties and function of multicomponent biological systems and processes. eLife publishes groundbreaking research in the life and biomedical sciences. All decisions are made by working scientists. WELCOME t is a pleasure to welcome you to Los Angeles and to the APS March I Meeting 2018. As has become a tradition, the March Meeting is a spectacular gathering of an enthusiastic group of scientists from diverse organizations and backgrounds who have broad interests in physics. This meeting provides us an opportunity to present exciting new work as well as to learn from others, and to meet up with colleagues and make new friends. While you are here, I encourage you to take every opportunity to experience the amazing science that envelops us at the meeting, and to enjoy the many additional professional and social gatherings offered. Additionally, this is a year for Strategic Planning for APS, when the membership will consider the evolving mission of APS and where we want to go as a society. -
PERSEVERANCE: Rocketing to Mars with STEM
PERSEVERANCE: Rocketing to Mars with STEM GRADE LEVELS MISSION This activity is appropriate for grades 3-8. Design fins for a foam rocket. VOCABULARY MATERIALS LAUNCH VEHICLE: A launch vehicle provides the velocity » 30 cm piece of polyethylene foam pipe insulation needed by a spacecraft to escape Earth’s gravity and set it (for 1/2” size pipe) on its course for space exploration. » Rubber band (size 64) TRAJECTORY: The path followed by a projectile flying or » Duct tape an object moving under the action of given forces. » Scissors » Meter stick/ruler » Two 4x6 index cards ABOUT THIS ACTIVITY On July 30, 2020, at 4:50 a.m., an Atlas V-541 rocket was launched from Cape Canaveral Air Force Station, Florida. The Atlas V is one of the largest rockets available for interplanetary flight and delivering things into space. The rocket departed Earth at a speed of about 24,600 mph (about 39,600 kph). Its launch was the start of the mission to deliver the Mars rover, Perseverance. After six-and-a-half months and about 300 million miles (480 million kilometers), the rover will reach Mars and land on the 28-mile-wide Jezero Crater (Feb. 18, 2021). Once the rover reaches Mars, its mission will be to look for signs of ancient life and collect samples of rock and soil. However, the rover could not do all of this important data collection without an energy source to power it. Idaho National Laboratory is playing a major role in powering Perseverance. INL’s Space Nuclear Power and Isotope Technologies Division assembles and tests Radioisotope Power Systems. -
Advanced Space Propulsion
ADVANCED SPACE PROPULSION Robert H. Frisbee, Ph.D. Jet Propulsion Laboratory California Institute of Technology Pasadena California Transportation Beyond 2000: Engineering Design for the Future September 26-28, 1995 693 ABSTRACT This presentation describes a number of advanced space propulsion technologies with the potential for meeting the need for dramatic reductions in the cost of access to space, and the need for new propulsion capabilities to enable bold new space exploration (and, ultimately, space exploitation) missions of the 21st century. For example, current Earth-to-orbit (e.g., low Earth orbit, LEO) launch costs are extremely high (ca. $10,000/kg); a factor 25 reduction (to ca. $400/kg) will be needed to produce the dramatic increases in space activities in both the civilian and overnment sectors identified in the Commercial Space Transportation Study (CSTS). imilarly, in the area of space exploration, all of the relatively "easy" missions (e.g., robotic flybys, inner solar system orbiters and landers; and piloted short-duration Lunar missions) have been done. Ambitious missions of the next century (e.g., robotic outer-planet orbiters/probes, landers, rovers, sample returns; and piloted long-duration Lunar and Mars missions) will require major improvements in propulsion capability. In some cases, advanced propulsion can enable a mission by making it faster or more affordable, and in some cases, by directly enabling the mission (e.g., interstellar missions). As a general rule, advanced propulsion systems are attractive because of their low operating costs (e.g., higher specific impulse, Isp) and typically show the most benefit for relatively "big" missions (i.e., missions with large payloads or &V, or a large overall mission model). -
Unit VI Superconductivity JIT Nashik Contents
Unit VI Superconductivity JIT Nashik Contents 1 Superconductivity 1 1.1 Classification ............................................. 1 1.2 Elementary properties of superconductors ............................... 2 1.2.1 Zero electrical DC resistance ................................. 2 1.2.2 Superconducting phase transition ............................... 3 1.2.3 Meissner effect ........................................ 3 1.2.4 London moment ....................................... 4 1.3 History of superconductivity ...................................... 4 1.3.1 London theory ........................................ 5 1.3.2 Conventional theories (1950s) ................................ 5 1.3.3 Further history ........................................ 5 1.4 High-temperature superconductivity .................................. 6 1.5 Applications .............................................. 6 1.6 Nobel Prizes for superconductivity .................................. 7 1.7 See also ................................................ 7 1.8 References ............................................... 8 1.9 Further reading ............................................ 10 1.10 External links ............................................. 10 2 Meissner effect 11 2.1 Explanation .............................................. 11 2.2 Perfect diamagnetism ......................................... 12 2.3 Consequences ............................................. 12 2.4 Paradigm for the Higgs mechanism .................................. 12 2.5 See also ............................................... -
Space Elevators: a Feasible Solution for Sending People and Goods Into Space More Cost Effectively
International Journal of Engineering Research and General Science Volume 3, Issue 5, September-October, 2015 ISSN 2091-2730 Space Elevators: A Feasible Solution for Sending People and Goods into Space More Cost Effectively Rupesh Aggarwal1, Pavleen Singh Bali2, Pranay Kami3, A.K. Raghav4 1Teaching Assistant, Department of Aerospace Engg. Amity University Gurgaon, Haryana, India 2Research Associate, Department of E & C Engg. Amity University Gurgaon, Haryana, India 3UG, Department of Aerospace Engg., Amity University Gurgaon, Haryana, India 4M.Tech. IISc Bangalore, Phd. IIT Delhi, Director- IR&D, Amity University Haryana, India Abstract— The Present study focuses on the fascinating concept of Space Elevators. Object of this study is to get introduced with every aspect in Designing, Working & Construction of Space Elevators. It‟s a concept in which tether is used to uplift any type of cargo or personnel from Earth surface to an orbit in space. Such invention not only becomes the new path for heavy loads to get into space but also becomes a cheap one. Also from the top of it, loads can be launch in any desired direction. By this not only the cost of the launch through rocket gets reduced but also the personnel handling this launch i.e. reduction of human error too. Perfect suitable material for such operation is Carbon Nano-tube which hundred times stronger and ten times lighter then Steel. In coming 50 years, it might be possible that many space elevators are ready to launch the spacecraft in space. Its application is not just only limited to the launching but also it can help in carrying heavy payloads to International Space Stations. -
Works of Love
reader.ad section 9/21/05 12:38 PM Page 2 AMAZING LIGHT: Visions for Discovery AN INTERNATIONAL SYMPOSIUM IN HONOR OF THE 90TH BIRTHDAY YEAR OF CHARLES TOWNES October 6-8, 2005 — University of California, Berkeley Amazing Light Symposium and Gala Celebration c/o Metanexus Institute 3624 Market Street, Suite 301, Philadelphia, PA 19104 215.789.2200, [email protected] www.foundationalquestions.net/townes Saturday, October 8, 2005 We explore. What path to explore is important, as well as what we notice along the path. And there are always unturned stones along even well-trod paths. Discovery awaits those who spot and take the trouble to turn the stones. -- Charles H. Townes Table of Contents Table of Contents.............................................................................................................. 3 Welcome Letter................................................................................................................. 5 Conference Supporters and Organizers ............................................................................ 7 Sponsors.......................................................................................................................... 13 Program Agenda ............................................................................................................. 29 Amazing Light Young Scholars Competition................................................................. 37 Amazing Light Laser Challenge Website Competition.................................................. 41 Foundational -
Mars Options
Spaceflight A British Interplanetary Society Publication Mars UK boosts options space spending NASA’s Radiation Atlantis threats display Shuttle: icon of an age Vol 60 No 8 September 2017 www.bis-space.com CONTENTS Editor: Published by the British Interplanetary Society David Baker, PhD, BSc, FBIS, FRHS Sub-editor: Volume 60 No. 9 September 2017 Ann Page Production Assistant: 331-334 Living with the Legend Ben Jones Author of the seminal work on NASA’s Space Shuttle, Dennis Jenkins describes how he came to follow the programme through work and, as Spaceflight Promotion: a genuine enthusiast, create the massive three-volume history of its Gillian Norman design evolution and engineering. Spaceflight Arthur C. Clarke House, 334 An icon immortalised 27/29 South Lambeth Road, Laurence Withers recounts a visit to the Kennedy Space Center where he London, SW8 1SZ, England. missed a launch and came across the Space Shuttle Atlantis, more by Tel: +44 (0)20 7735 3160 Fax: +44 (0)20 7582 7167 mistake than by pre-planning, to impress and astound with its display of Email: [email protected] space artefacts. www.bis-space.com 336-342 Evaluating Mars Programme Designs ADVERTISING Stephen Ashworth has a particular view on Mars missions and judges a Tel: +44 (0)1424 883401 range of potential expeditionary modes to comment on the architecture Email: [email protected] being discussed by government agencies DISTRIBUTION and commercial providers alike. Spaceflight may be received worldwide by mail through membership of the British Interplanetary Society. Details including Library subscriptions are available from the above address. -
Achievable Space Elevators for Space Transportation and Starship
1991012826-321 :1 TRANSPORTATIONACHIEVABLE SPACEAND ELEVATORSTARSHIPSACCELERATFOR SP_CEION ._ Fl_t_ Dynamic_L',_rator_ N91-22162 Wright-PattersonAFB,Ohio ABSTRACT Spaceelevatorconceptslorlow-costspacelau,'x,,hea_rereviewed.Previousconceptssuffered;rein requirementsforultra-high-strengthmaterials,dynamicallyunstablesystems,orfromdangerofoollisionwith spacedeb._s.Theuseofmagneticgrain_reams,firstF_posedby BenoitLeben,solvestheseproblems. Magneticgrain_reamscansupportshortspace6!evatorsforliftingpayloadscheaplyintoEarthorbit, overcomingthematerialstrengthp_Oiemin.buildingspaceelevators.Alternatively,thestreamcouldsupport an internationaspaceportl circling__heEarthdailyt_nsofmilesabovetheequator,accessibleto adv_ncad aircraft.Marscouldbe equippedwitha similargrainstream,usingmaterialfromitsmoonsPhobosandDefines. Grain-streamarcsaboutthesuncould_ usedforfastlaunchestotheouterplanetsandforaccelerating starshipsto nearikjhtspeedforinterstella:recor_naisar',cGraie. nstreamsareessentiallyimperviousto collisions,andcouldreducethecost_f spacetranspo_ationbyan o_er c,,fmagnih_e. iNTRODUCTION Themajorob_,tacletorapi( spacedevei,apmentisthehighco_ oflaunct_!,'D_gayloadsintoEarthorbit. Currentlaunchcostsare morethan_3000per kilogramand, rocketvehicles_ch asNASP,S,_nger_,'_the AdvancedLaunchSystemwiltstillcost$500perkilogram.Theprospectsforspaceente_dseandsettlement. arenotgoodunlessthesehighlaunchc_stsarereducedsignificantly. Overthepastthirtyyears,severalconceptshavebeendevelopedforlaunchir_la{_opayloadsintoEarth orbitcheaplyusing"_rJeceelevators."The._estructurescanbesupportedbyeithe.rs_ati,for:: -
Amusementtodaycom
KINGS ISLAND’S 40th ANNIVERSARY – PAGES 19-22 TM Vol. 16 • Issue 3 JUNE 2012 Two traditional parks turn to Zamperla for thrill factor AirRace takes flight at Utah’s Lagoon Massive Black Widow swings into historic Kennywood Park FARMINGTON, Utah — Inspired by what they saw at Co- STORY: Scott Rutherford ney Island’s Luna Park last year, Lagoon officials called upon [email protected] Zamperla to create for them a version of the Italian ride manu- WEST MIFFLIN, Pa. — facturer’s spectacular AirRace attraction. Guests visiting Kennywood Just as with the proptype AirRace at Luna Park, Lagoon’s Park this season will find new ride replicates the thrill and sensations of an acrobatic air- something decidedly sinister plane flight with maneuvers such as banks, loops and dives. lurking in the back corner of Accommodating up to 24 riders in six four-seater airplane- Lost Kennywood. The park’s shaped gondolas, AirRace combines a six-rpm rotation with a newest addition to its impres- motor driven sweep undulation that provides various multi- sive ride arsenal is Black vectored sensations. The gondolas reach a maximum height of Widow, a Zamperla Giant 26 feet above the ground while ‘pilots’ feel the acceleration of Discovery 40 swinging pen- almost four Gs, both right-side-up and inverted. The over-the- dulum ride. shoulder restraint incorporated into the seats holds riders during Overlooking the the simulated flight, and with a minimum height requirement of final swoop turn of the just 48 inches, AirRace is one of Lagoon’s most accessible family Phantom’s Revenge and the thrill rides.