Simulations show a single photon can simultaneously excite two atoms

first_img © 2016 Phys.org Journal information: Physical Review Letters Scientists have known for several years that it is possible to have a single atom absorb two photons, causing it to move to a higher energy state. The process has actually been observed many times and is now used in microscopy and spectroscopy—its reverse, extracting the two photons from a single atom, has also been used as a means for producing entangled photons. In this new effort, the researchers wanted to know if the same would hold true for causing a single photon to be absorbed by two different atoms—theory has already suggested it should be possible.To find out, the team created a simulation in which two atoms were held in place by mirrors inside of a chamber—creating a virtual optical cavity. They reasoned that the size of the cavity should be based on the frequency and wavelength of the photon that would be introduced (i.e. it should be double that of the photon). They then introduced the photon and found that in such a circumstance, both atoms were able to absorb the photon—each grabbing half of its energy—and moving into a higher energy state. And because the process could be reversed—the two atoms together producing a single photon, the team believes it might be possible to use the phenomenon in a quantum system—one of the atoms would theoretically serve as a qubit, carrying information. To give up its information, the qubit would move the information to the cavity where the second atom could be used to control transmission.The researchers found that the simulation worked for three atoms and one photon, as well—the energy from the photon was equally divided between the atoms. Sharing the limelight. Two or more atoms in an optical cavity can absorb a single photon, according to theory. The cavity allows standing light waves of a single frequency (red glow), which can be limited to one photon. Credit: APS/Joan Tycko/via Physics, 9, 83. Explore further , arXiv More information: Luigi Garziano et al. One Photon Can Simultaneously Excite Two or More Atoms, Physical Review Letters (2016). DOI: 10.1103/PhysRevLett.117.043601 , On Arxiv: https://arxiv.org/abs/1601.00886ABSTRACTWe consider two separate atoms interacting with a single-mode optical or microwave resonator. When the frequency of the resonator field is twice the atomic transition frequency, we show that there exists a resonant coupling between one photon and two atoms, via intermediate virtual states connected by counterrotating processes. If the resonator is prepared in its one-photon state, the photon can be jointly absorbed by the two atoms in their ground state which will both reach their excited state with a probability close to one. Like ordinary quantum Rabi oscillations, this process is coherent and reversible, so that two atoms in their excited state will undergo a downward transition jointly emitting a single cavity photon. This joint absorption and emission process can also occur with three atoms. The parameters used to investigate this process correspond to experimentally demonstrated values in circuit quantum electrodynamics systems. Researchers discover a way to avoid decoherence in a quantum system Citation: Simulations show a single photon can simultaneously excite two atoms (2016, August 5) retrieved 18 August 2019 from https://phys.org/news/2016-08-simulations-photon-simultaneously-atoms.html (Phys.org)—A small team of researchers with affiliations to institutions in Italy, Japan and the U.S. has created a simulation that suggests that it should be possible for a single photon to simultaneously excite two atoms. In their paper published in the open access journal Physical Review Letters, the team describes the process leading to their simulation, what it showed and why they believe their findings have applications in quantum computers. 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.last_img read more

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Therapeuticsonachip TOC Manufacturing synthetic proteins for pointofcare therapeutics

center_img After CFPS+P workflow optimization using GFP, the scientists used the same setup to optimize the conditions to synthesize cecropin B. By following the steps of expression, purification, electrophoresis and staining in the setup, Murphy et al. confirmed the successful production and purification of cecropin B and recovered soluble proteins to elute 63 ng/µL, with a purity of 92 percent. They then tested the bioactivity of cecropin B relative to E. coli inhibition to demonstrate successful antibiotic activity by inhibiting bacterial growth. In this way, therapeutic proteins synthesized and purified using the microfluidic setup demonstrated active and effective suppression of bacterial growth. The cost-effective system can be actively integrated in low resource environments for frugal science. Murphy et al. intend to completely automate the system based on ongoing optimizations in the future. They envision applications of the setup to engineer a range of diverse therapeutic proteins for cost-effective point-of-care production. Journal information: Small , Nature Biomedical Engineering Simplified method makes cell-free protein synthesis more flexible and accessible Among the proteins examined in the study, cecropin B has a minimum inhibitory concentration of 9.5 ng/µL to exert antimicrobial effects. Using the microfluidic setup, the scientists combined protein synthesis and purification to produce an antimicrobial peptide cecropin B at a clinically relevant dose (63 ng/µL). The continuous-flow production in the setup was completed in three developmental phases: Cell-free protein synthesis (CFPS) reactor designPurification reactor (P) designIntegrated CFPS+P system designMurphy et al. used soft-lithography based polydimethylsiloxane (PMDS) molding to fabricate the devices; building multilayers using micromechanical valves. During the first stage of device design in the CFPS reactor, the scientists fabricated a serpentine channel microfluidic chip, similar to previous studies for on-chip protein synthesis. The microfluidic device contained inlets connected to a syringe pump placed on the heating stage of a microscope, where three inlets received (1) cell lysate, (2) CFPS reaction buffer and a (3) DNA template into the long serpentine channel (approximating 130 cm) with one outlet. The scientists fed the three reaction components at a combined flow rate of 0.15 µL/min driven by a syringe pump for a residence time of 1.5 hours. They heated the reactor with a stage heater (37 degrees C) and modeled the setup using COMSOL Multiphysics software to verify device mechanics, for optimal on-chip diffusion-based mixing and reaction. To validate the operating principles of the device, Murphy et al. synthesized the reporter protein, GFP using a variety of DNA templates. The system produced volumes of protein at a constant reaction time. , Cell Provided by Science X Network 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. More information: Travis W. Murphy et al. On-chip manufacturing of synthetic proteins for point-of-care therapeutics, Microsystems & Nanoengineering (2019). DOI: 10.1038/s41378-019-0051-8 Andrea C. Timm et al. Toward Microfluidic Reactors for Cell-Free Protein Synthesis at the Point-of-Care, Small (2015). DOI: 10.1002/smll.201502764 Keith Pardee et al. Portable, On-Demand Biomolecular Manufacturing, Cell (2016). DOI: 10.1016/j.cell.2016.09.013 Sai Ma et al. Cell-type-specific brain methylomes profiled via ultralow-input microfluidics, Nature Biomedical Engineering (2018). DOI: 10.1038/s41551-018-0204-3 Therapeutic proteins are protein-based drug candidates bioengineered in the lab for pharmaceutical and clinical applications. Based on their pharmacokinetics, the candidates can be divided into groups that (1) replace a defective or abnormal protein, (2) augment an existing path in vivo, (3) provide a new function or activity in vivo, (4) interfere with activities of a molecule or organism and (5) deliver encapsulated proteins or compounds including, cytotoxic drugs, radionuclide or effector proteins.last_img read more

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Arms smuggling case STF team heads out to Bihar

first_imgKolkata: A team of the Special Task Force (STF) of Kolkata Police has set out for Bihar to further probe in connection with the incident in which firearms from Rifle Factory Ishapore were smuggled to Maoists.The police decided to go to Bihar for investigation into the case, anticipating that the matter was not limited to smuggling of firearms to Maoists or anti-social groups in Bihar, but also to the rebel groups in the North East.The police have arrested six persons, including two from Bihar – Ajay Pandey alias Guddu Pandit and Jaysankar Pandey. Also Read – Heavy rain hits traffic, flightsThe police are considering Guddu to be one of the main persons behind the operation of the entire racket that had been operating from Bihar, with Jaysankar being one of his associates.Investigation has revealed that like Jaysankar, Guddu had many other close aides who used to look after the deals with the insurgent groups from North East. The police had also come to know that they used to get bullets from their counterparts in Punjab. The police are now trying to arrest the close aides of Guddu and at the same time, trying to find out who were helping them to get bullets from Punjab. Also Read – Speeding Jaguar crashes into Merc, 2 B’deshi bystanders killedIt may be mentioned that the police have reconstructed the plot on Tuesday. The police had taken Bhola, who was also arrested, to Rifle Factory Ishapore for reconstruction of the plot, following which they came to know about the involvement of some more officials of the rifle factory. The police have already arrested two officials of the rifle factory on Monday.The officials were summoned and they were also questioned in this connection, sources said, adding that the police have come to know about some more persons, who also hail from Bihar. Subsequently, a team comprising senior officers of STF was sent to Bihar and it has been learnt that they would be conducting raids at different places, including Patna and Nawada.During reconstruction of the plot on Tuesday, police have spotted the window from where they used to throw scrap firearms out of the room where it was stored. There was a huge quan-tity of firearms piled up in the storerooms. The police have also identified the places from where they used to scale the walls of the rifle factory, to avoid getting noticed while taking firearms out of the place.last_img read more

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Showcasing the best of Bali

first_imgBali resembles India in terms of culture as they have 95 per cent Hindu population but to know more about them, one has to visit the country and its exotic locations. For those who wish to know more about the culture, one can look at the photographs that will be showcased in an exhibition in the national Capital. The exhibition titled- ‘Women In Bali,’ which will begin on April 26, contains series of photographs that attempt to make a comparison of the role of women in India and Bali— two nations permeated by the same religious traditions. It also aims to reflect on the opportunity present for the women in society. Also Read – ‘Playing Jojo was emotionally exhausting’The narration of the exhibition flows through a kaleidoscope of women, immersed in their natural environment, in everyday life or portrayed in composite form. The images talk about an intertwining of existences that gradually expresses female role-play, a cultural pluralism, spiritual intensity and the importance of nature. Some of the images are imbued with a feeling of sacredness. The woman bowing her head in deep respect under a cascade of silver, the subject holding out her hand as crystal clear water gushes over it- which puts into focus the woman engaged in tending to an inundated rice field, juxtaposing not just the various roles of water but of the women as well. Also Read – Leslie doing new comedy special with NetflixElaborating more about her work, Bruna says, “The exhibition and the book seek to be homage to the island and all the women who live there. Over time, I have met many women, both from Bali and elsewhere, who have launched important artistic, ethical and social projects on the island. Through their portraits I have tried to grasp their essence, describing the force of the female energy symbolised by water, the holy water, a vehicle of ancient memories and an instrument of healing.” “Bali is a living island, a place that has always stirred in me contrasting emotions, stimulated by its fluid and changeable light, by a rituality made up of gestures that render the invisible visible and, above all, by a diffuse beauty that reflects a harmony that is continually reinvented”, adds Bruna Rotunno. The soundtrack for the exhibition has been composed by Eraldo Bernocchi, an Italian musician, producer and sound designer. The exhibition has been curated by Singapore based art consultant Sabiana Paoli in association with art historian Dr Alka Pande. Speaking about the artist’s work, Sabiana shares, “Bruna Rotunno’s affair with the island of Bali started 30 years ago, when she visited the islands for the first time. In a project spanning eight years, she has organised her gaze into a story in pictures where every gesture and every figure meticulously translates the essence of a unique place, characterised by a fluid and harmonious energy.”‘Women In Bali’ reflects the twin worlds of advertising and fashion through the pictures. The portraits of women pursue the mundane appear like finely finished stylish fashion pictures.last_img read more

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Creative Magnifier

first_imgUNICEF India and BBC Media Action India today launched a ‘coming of age’ action drama series for social change– AdhaFULL. The launch was graced by Dr A Surya Prakash, Chairman, Prasar Bharati, Louis-Georges Arsenault, UNICEF India Representative, Supriya Sahu, Director General Doordarshan, Priyanka Dutt, Country Director, BBC Media Action, officials from the Government of India, senior members from the media,civil society partners and adolescents themselves.  Also Read – Add new books to your shelfAdhaFULL, a 78 episode TV series, has been conceptualized and created by BBC Media Action, and developed in partnership with UNICEF. AdhaFULL follows three adolescents—Kitty (16), Tara (11) and Adrak (15), who form the AdhaFULL gang, as they solve a new case each week. The mysteries are intertwined with their journey of growing up in a small town. Issues such as under-age marriage, nutrition, stereotyping of girls and boys, continuing education, peer pressure, school drop-outs and exam blues and gender-based violence are creatively depicted in the narrative.  Also Read – Over 2 hours screen time daily will make your kids impulsiveSpeaking on the occasion, Louis-Georges Arsenault, UNICEF India Representative, said, “India is home to 243 million adolescents. This series portrays adolescents who stand up for their rights. Through a mix of social drama, action, energy, fun, humour and emotions, this edutainment package discusses existing social norms and showcases transformation from a culture of silence to a culture of change and freedom”The half-hour-long episodes of AdhaFULL, will be telecast on Doordarshan National on Friday, Saturday and Sunday every week between 7.30-8pm from October 21 onwards. “Doordarshan has the largest reach in India. We are happy to be the first channel to broadcast a dedicated programme for adolescents, engaging them so that they can reach their full potential”, said Dr A Surya Prakash, Chairman, Prasar Bharati. ‘AdhaFULL’, the Hinglish name of the series, reflects the hybrid nature of both a society in transition and adolescence. The ‘AdhaFULL’ gang episodes swing between its rural avtaar of the past and its present small town persona with urban trappings. “Young lives and aspirations are about the 3Cs – curiosity, challenge and creativity. Through AdhaFULL’s story and its characters, we want to engage our young viewers and their parents in a journey of change, so that they feel they can negotiate and work with the 3Cs”, says Radharani Mitra, Executive Producer, BBC Media Action.last_img read more

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Congress hails Priyankas appointment as general secretary for UP East

first_imgKolkata: The West Bengal unit of Congress on Wednesday welcomed Priyanka Gandhi Vadra’s appointment as general secretary for Uttar Pradesh East, and said it would boost the morale of the party ahead of the Lok Sabha polls. Ending years of speculation, Priyanka Gandhi formally entered politics in a move reflecting the party’s intent to go full throttle in the state ahead of the general elections. “We welcome Priyanka Gandhi Vadra’s appointment as Congress general secretary, as it would further boost the morale of the party ahead of Lok Sabha polls. Also Read – Speeding Jaguar crashes into Mercedes car in Kolkata, 2 pedestrians killed”This move will also further strengthen the organisation in the country, especially Uttar Pradesh,” senior Congress leader and MP Pradip Bhattacharya said. Several other top state Congress leaders, too, welcomed the move and congratulated Priyanka Gandhi. Carrying posters of Congress president Rahul Gandhi and Priyanka Gandhi, West Bengal Congress workers in different parts of the state celebrated her appointment by distributing sweets and bursting crackers.last_img read more

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