Making Quantum Behavior Observable Using Optical Levitation

first_img Citation: Making Quantum Behavior Observable Using Optical Levitation (2010, January 26) retrieved 18 August 2019 from https://phys.org/news/2010-01-quantum-behavior-optical-levitation.html Physicists propose quantum entanglement for motion of microscopic objects In the new study, Chang and his coauthors have proposed a novel approach in which one isolates the system from the environment to such a degree that re-heating becomes a very inefficient process, even when the environment sits at room temperature. In this scheme, isolation is achieved by optically levitating an entire nano-mechanical system inside an optical cavity, which removes direct contact of the system with any other material. An optical cavity consists of an arrangement of mirrors that confines light inside of it by repeatedly reflecting the light waves off the mirrors. The force from the light is powerful enough to counteract the force of gravity, creating an optical trap that can suspend small, light-weight objects inside the cavity.The researchers calculated that an optically levitated silica nanosphere can be optically self-cooled to its ground state starting from room temperature. In this scenario, the nanosphere would interact with two optical modes of the cavity. One mode would provide an optical trap for the sphere, while a second, weaker mode would provide a radiation pressure cooling force. The scientists explain that this system is an extreme example of environmental isolation in which the nanosphere is mechanically isolated as well as thermally decoupled from its surroundings. In fact, the isolation is so good that quantum mechanical effects should be able to persist for times much longer than in conventional nano-mechanical systems, even those in cryogenic environments. While ground-state cooling should also be achievable in the near future with other systems, the scientists believe that the levitated system is an elegant example of how quantum effects can emerge and be robust even at room temperature. For example, the scientists predict that quantum entanglement initially shared between two light modes could be transferred onto the motion of two nanospheres trapped in separate cavities, which could then be observed. Other potential applications include exploring fundamental material limits, investigating nanoscale properties, and realizing novel quantum hybrid architectures.“There are a number of potential applications for quantum opto-mechanical systems,” Chang said. “One can imagine coupling such systems to other quantum systems to enable tasks such as quantum information transfer or quantum state manipulation. For example, work along these lines has been done by Dan Rugar at IBM, who has pioneered techniques to detect single electron spins in solid-state environments using opto-mechanics. It is also possible that opto-mechanical systems can be used as a novel platform for realizing nonlinear optical processes, by suitable manipulation of the interaction between light and mechanical motion.” Explore further The researchers, Darrick E. Chang, et al., from institutions in the US and Austria, are publishing their study in an upcoming issue of the Proceedings of the National Academy of Sciences. A similar proposal has simultaneously been put forth by researchers at the Max Planck Institute in Garching, Germany.“Over the next several years, there will be a concerted effort by a number of groups worldwide to observe and manipulate quantum behavior in progressively larger and more complex mechanical systems,” Chang, from the California Institute of Technology, told PhysOrg.com. “A major obstacle is the interaction between these systems and their environments, which tends to ‘leak away’ the quantum nature of these systems and return them to classical states. We’ve proposed a technique that can allow these interactions to be dramatically suppressed, by using optical forces to levitate such systems and remove them from any direct contact with material surroundings. We have shown in detail that this enables quantum behavior to emerge in the case of a levitated nanosphere, but we anticipate that these ideas can also be applied to a wide class of other systems and over a large range of system size scales.”As the scientists explain, in order to make a system’s quantum behavior observable, the system must be actively cooled to temperatures much colder than the surrounding environment. A key challenge to this cooling is overcoming the tendency of the environment to re-heat the system back to the ambient temperature. One possible solution is to work in cryogenic environments where the ambient temperature itself is reduced, an approach that is being taken by a number of groups worldwide. “Using cryogenic setups is certainly a viable approach to reduce the effects of the environment,” Chang said. “As one attempts to observe more exotic quantum effects and use larger systems, however, it is likely that moving to cryogenic environments alone will not be sufficient. This motivates the search for other techniques to suppress environmental interactions, which can be applied as an alternative or in conjunction with cryogenics.” This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.center_img Copyright 2010 PhysOrg.com. All rights reserved. This material may not be published, broadcast, rewritten or redistributed in whole or part without the express written permission of PhysOrg.com. More information: D. E. Chang, et al. “Cavity opto-mechanics using an optically levitated nanosphere.” Proceedings of the National Academy of Sciences. doi:10.1073/pnas.0912969107 A dielectric sphere trapped in an optical cavity can enable quantum behavior to emerge. The large trapping beam intensity (red) provides an optical potential that traps the sphere near an antinode. A second, weaker cavity mode (green) cools the motion of the sphere. Image credit: D. E. Chang, et al. (PhysOrg.com) — Perhaps one of the biggest challenges of modern physics is figuring out how to realize and take advantage of strange quantum behaviors in progressively larger and more complex systems. Progress along this front is expected to shed insight into the nature of quantum mechanics and lead to many novel applications. With this goal in mind, scientists have recently proposed a unique approach that involves optically levitating a nano-mechanical system in order to cool it to its quantum ground state, where the amount of motion of the system reaches the fundamental minimum set by intrinsic quantum fluctuations.last_img read more

Research team finds new explanation for Cambrian explosion

first_imgFossil of Marrella splendens (Marrellomorpha). Image: Wikipedia. (PhysOrg.com) — For hundreds of years, researchers from many branches of science have sought to explain the veritable explosion in diversity in animal organisms that started approximately 541 million years ago here on planet Earth. Known as the Cambrian period, it was the time, according to fossil evidence, when life evolved from simple one celled organisms, to creatures that had multiple cells with varied functions. Now, new evidence by a team of biologists, paleobiologists and ecologists suggests that the sudden explosion of new life forms may not have been so sudden after all. In their paper published in Science, the teams says that it appears likely that most of the new life forms that show up in fossil finds, were well on their way to development before the Cambrian period and that many of them, by their behaviors, may have helped pave the way for others. Fossils show earliest animal trails To better understand what was happening before and during the Cambrian period, the team took a two-pronged approach: one side studied, compiled and updated the fossil evidence, while the other focused on the molecular makeup of various organisms to uncover their gene history to create a more precise family tree. By combining the evidence from both sides, the team was able to put together a picture of what they believe went on.From their work it appears that the basic genetic components for the organisms that seemingly sprang into existence during the Cambrian period were in place long before the fossil records show. In fact, there appeared to be evidence of a slow march of development for 200 million years before the sudden diversity became evident, which indicates that many such organisms were slowly evolving and only showed when conditions became ripe.The team suggests that for many of those 200 million years, Earth went through some very cold periods where the entire planet was likely frozen, stagnating development. Then, there came a time of warming, partly brought about, they theorize, by the development of organisms that were capable of changing the environment by pulling carbon from seawater and releasing more oxygen when they died and also by those that burrowed into the seafloor aerating it, providing a new type of environment for new types of organisms.As more organisms developed, environmental conditions changed as a result, allowing for more diversity and so on and so forth through the Cambrian period, resulting in the explosion of all those new kinds of life forms that scientists have been puzzling over for years. Journal information: Science Citation: Research team finds new explanation for Cambrian explosion (2011, November 29) retrieved 18 August 2019 from https://phys.org/news/2011-11-team-explanation-cambrian-explosion.htmlcenter_img © 2011 PhysOrg.com This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. Explore further More information: The Cambrian Conundrum: Early Divergence and Later Ecological Success in the Early History of Animals, Science 25 November 2011: Vol. 334 no. 6059 pp. 1091-1097 DOI: 10.1126/science.1206375ABSTRACTDiverse bilaterian clades emerged apparently within a few million years during the early Cambrian, and various environmental, developmental, and ecological causes have been proposed to explain this abrupt appearance. A compilation of the patterns of fossil and molecular diversification, comparative developmental data, and information on ecological feeding strategies indicate that the major animal clades diverged many tens of millions of years before their first appearance in the fossil record, demonstrating a macroevolutionary lag between the establishment of their developmental toolkits during the Cryogenian [(850 to 635 million years ago (Ma)], and the later ecological success of metazoans during the Ediacaran (635 to 541 Ma) and Cambrian (541 to 488 Ma) periods. We argue that this diversification involved new forms of developmental regulation, as well as innovations in networks of ecological interaction within the context of permissive environmental circumstances.last_img read more

Toward a better understanding of structuremetabolism relationships in human aldehyde oxidase Update

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Summer plans

first_imgThis summer presents an opportunity for children to develop their skills and discover new talents through filmmaking with Cinedarbaar’s 5th Summer Film Camp, being held from 19 to 30 May 2014 (Monday – Friday) at S-280, Greater Kailash – 1. The theme of this year’s camp is Literary Adaptation, hence encouraging them to read too and convert the read stories into an audio visual medium.Vacations are the only time when children can look to activities that are not part of the school curriculum but interests them. The 5th Summer Film Camp by Cinedarbaar, will help children explore an art form which will not only help them develop new skills but also challenge their creativity and imagination. Also Read – ‘Playing Jojo was emotionally exhausting’The two-week long journey will focus on skills such as acting, story writing, story-boarding, directing, editing, shooting and photography. The camp will assist children to develop leadership skills by allowing them to work in teams and enhance their creativity through performance and writing art.The students will also learn about the difference between writing for a book and for cinema. Each day the story and dialogues will be created by children to be implemented through a short film. This film will feature all the students of the camp where they will act in it, write it and shoot it.There will be 2 batches: Junior Batch and a Senior Batch. So get in touch with them for more details!last_img read more

China bodysearches 10000 pigeons before National Day

first_imgThe symbols of peace were released at sunrise in Beijing’s symbolic heart of Tiananmen Square in a ceremony for the 1 Oct. holiday to celebrate the 65th anniversary of the founding of the People’s Republic of China. Beijing domestic security police officer was quoted in the Jinghua Times as saying workers checked the wings, legs and anus of each pigeon ahead of time to ensure they were ‘not carrying suspicious material.’ The entire process was videotaped, and the birds were then loaded into sealed vehicles for the trip to Tiananmen Square, the newspaper said. A similar report appeared in the Beijing News, and the People’s Daily tweeted about it in English: ‘10,000 pigeons go through anal security check for suspicious objects on Tuesday, ready to be released on National Day on Wednesday.’The reports – which did not say what the suspicious materials might be – drew amused and derisive responses from some Chinese readers.last_img read more

Chekhov classics come alive

first_imgChekhov Republic is an adaptation of Anton Chekhov’s four classic stories which are deceptively simple but often end on an abrupt note. Directed by Devesh Nigam, the act was staged at Akshara Theatre on April 26. The play was an amalgation of four classic plays. The first was The Proposal is a one-act comical farce which shows the characters’ desperation for marriage. The dialogue-based action and situation based humor portrays how economic security takes precedence over romance and love. Surgery is a story of a man with a toothache and an inexperienced dental assistant who attempts his first tooth examination!  Also Read – ‘Playing Jojo was emotionally exhausting’The Drowned Man is a black comedy. It’s a weird tale of a man who stages drowning act for meager sum for meeting ends . On the Harmful Effects of Tobacco is a hilarious monologue which is rarely seen on stage nowdays. A man has been commanded by his wife to give a lecture on ‘the harmful effects of tobacco,’ although he himself is a chain smoker!. He obeys but digress from the actual subject by complaining about his domineering wife. The cast of the play were  Atul, Zubair, Abhishek Mehta, Anisha, Amit Pandey, Shorya Sehgal, Satyendra Yadav, Ashish Mishra, Komal Gupta, Neelesh Bisht, Deep Singh, Rohit Shukla, Rohit Kumar. The play was a presentation of Cineaste’ group which is a Delhi based theatre group formed in 2011. The group is a bunch of passionate people, from working professionals, students to the aspirants.last_img read more

Fire breaks out in moving bus

first_imgKolkata: a fire broke out in a moving bus on Sunday morning at Kaikhali. After the driver of the bus noticed a spark and smoke coming out of the battery, he managed to stop and evacuate the bus. No injury reported in this incident.According to locals, around 9 am, a West Bengal Transport Corporation (WBTC) bus of S-37A route was approaching Kaikhali bus stop, they noticed smoke coming out of the battery box. The driver also noticed that the temperature inside the bus was a bit high. Suddenly he noticed spark on the dashboard. Also Read – Rain batters Kolkata, cripples normal lifeSensing danger, the driver stopped the bus just before the Kaikhali bus stoppage and instructed the passengers to get down immediately.As soon as the bus was evacuated, the fire broke out at the front portion of the bus.On duty traffic police personnel immediately segregated the burning bus with multiple guard rails. As the fire spread, vehicular movement was stopped from 45 bus stand towards Baguiati. All the Baguati-bound vehicles were diverted using a lane on the airport-bound flank from 45 bus stand.Upon being informed two fire tenders reached the spot and doused the flames within a short period of time. However, the whole bus got badly damaged. The bus has been removed and normal traffic movement was restored around 9:45 am. According to the fire fighters, the electrical wiring or the battery of the bus might have caused short circuit.last_img read more

Amidst mudras and raagas

first_imgMusic and dance are dependent on each other and to showcase the smooth amalgamation of the two art forms and its nuances, Rhythm Society is going to present ‘Smriti 2016’ -an Indian classical music and dance festival in the national Capital and Dehradun.‘Smriti’ is  a four-day Indian classical music and dance festival. It is a gateway for propagating traditional music and performing arts, to widen up the horizon of the people by facilitating them with a platform.  Also Read – ‘Playing Jojo was emotionally exhausting’Their main motive is to spread better understanding about diverse cultural heritage and to evolve the art form. The festival will be a blend of country’s eminent maestros, with the vibrancy of exceptional young talents, without alienating the intrinsic heritage and successfully meeting the challenge of enjoying unabated opportunity.Smriti 2016 will stage some iconic jugalbandis, collaborative infusions with folk, captivating tribal martial dance and a mesmerising classical Kathak recital, carrying forward the culture of bringing together the young talented mavens and maestros together. Also Read – Leslie doing new comedy special with NetflixThe young Sitar-Sarod duo- Aayush Mohan Gupta and Lakshya Mohan Gupta will be opening the festival and will be accompanied by Tabla artist, Abhishek Mishra.The first day of the festival will have a genre of Indian tribal martial dance form Mayurbhanj Chhau presented by the royal ancestry of renowned Mayurbhanj Chhau performers and the grandsons of Sangeet Natak Academy awardee, Guru Anant Charan Saibabu. They will be accompanied by a group of talented dancers from Gurukul Chhau Dance Sangam. The second day of the festival will have ‘Desert Storm’, a unique concept that brings the best of multi genre, intermingling the rustic charms of the deserts with the classical Indian music performed by the maestros, Pandit Salil Bhatt (Satvik Veena), disciple of Grammy awardee Pandit Vishwa Mohan Bhatt, Pandit Udai Mazudmar (Tabla) of Benaras gharana and the Manganiyars of Rajasthan – Kutla Khan (Khartaal), Roshan Khan (vocals/Harmonium) and Goram Khan (Dholak).The festival will come to an end with the enthralling and mesmerising Kathak dance recital by Namrta Rai, disciple of Late Dr Madhukar Anand and Pandit Udai Mazumdar.last_img read more