|장소||E6-2. 1st fl. #1323|
|일시||Oct. 18 (Tue.), 3PM|
|연사||Dr. JunHo Suh, Korea Research Institute of Standards and Science|
“Hybrid quantum systems with mechanical oscillators”
Dr. JunHo Suh, Korea Research Institute of Standards and Science
Oct. 18 (Tue.), 3PM, E6-2. 1st fl. #1323
Quantum machines are actively pursued to harness quantum coherence and entanglement as new resources for information processing and precision sensing. Among those activities, hybrid quantum systems are recognized as a promising platform for building multi-functional quantum machines by connecting quantum states in different physical domains, and mechanical oscillators are accepted as important components in the quantum hybrids. In this talk, I review recent examples of hybrid quantum systems involving mechanical oscillators strongly coupled to electrons and photons. In the first part, a quantum electro-mechanical system is introduced. A cooper-pair box qubit is electrostatically coupled to a nanomechanical oscillator. A dispersive measurement of qubit states is achievable through high-quality read-out of nanomechanical motion, which also maintains qubit coherence proved via microwave spectroscopy and Landau-Zener interference. In the second part, mechanical oscillators coupled to microwave photons, or "quantum opto-mechanical systems", are described, where radiation pressure mediates the interaction between photons and the mechanical oscillator. Photons act as a probe for mechanical motion in this case, and a fundamental limit in measurement sensitivity arises due to Heisenberg's uncertainty principle, as known as quantum standard limit(SQL). By carefully measuring mechanical motion in quadratures, we identify the fundamental back-action from photons which mandates SQL, and also demonstrate a novel scheme known as quantum non-demolition measurement (QND) which allows a precise measurement without back-action in one quadrature of motion. When the coupling between the microwave photons and mechanical motion is strong enough, the back-action from photons start modifying quantum noise in mechanical oscillators and produced mechanical quantum squeezed states[4,5]. Finally, it is expected that one could approach ultra-strong coupling regime as photon-mechanical oscillator coupling strength increases, where single photon coupled to mechanical motion dominates the hybrid system. Mechanical states in the ultra-strong coupling limit deviate from well-known number states which could open a new paradigm for controlling mechanical quantum states. A quantum dot system embedded in a nanowire is proposed to be a candidate to reach this interesting regime, and our recent progress toward this direction is dissussed.
 Kurizki et.al., PNAS 112, 3866-3873 (2015).
 LaHaye et.al., Nature 459, 960-964 (2009).
 Suh et.al., Science 344, 1262-1265 (2014).
 Wollman et.al., Science 349, 952-955 (2015).
 Lei et.al., PRL 117, 100801 (2016).
 Nation et.al., PRA 93, 022510 (2016).
Contact: SunYoung Choi, (email@example.com)
Center for Quantum Coherence in Condensed Matter, KAIST
|공지||2017/09/14 - 12/07||Seminar Room #1323||Prof. 정광용 교수(Gacheon Univ) and etc.||Fall 2017: Physics Seminar Serises|
|공지||2017/09/04 - 12/04||Seminar Room 1501||Prof. Sangsu Bae(Hanyang Univ.) and etc.||Fall 2017: Physics Colloquium|
|103||Nov. 1st (Tue), 10:30AM||#1323(E6-2 1st fl.)||Dr. Gadi Eisenstein, Technion||Time scale dependent dynamics in InAs/InP quantum dot gain media|
|102||Oct. 27th(Thu) 4PM||#1323(E6-2)||Dr. 이 강 희, KAIST, Mechnical Engineering||Terahertz Metal Optics|
|101||Nov. 1 (Tue.) 2:30 pm||Seminar Room #1323(E6-2)||Prof. Youngjoon Kwon, Yonsei Univ.||Search for dark sector particles in the B-factory experiments|
|100||Oct. 17th (Mon) 11:00 AM||#1323,(E6-2, 1st fl.)||Nguyen Quang Liem, Institute of Materials Science, VAST, Viettnam||IMS and examples of the studies on optoelectronic materials|
|»||Oct. 18 (Tue.), 3PM||E6-2. 1st fl. #1323||Dr. JunHo Suh, Korea Research Institute of Standards and Science||“Hybrid quantum systems with mechanical oscillators”|
|98||Oct. 18 (Tue.), 1:30 PM||1st fl. #1323(E6-2)||Dr. Chan-Ho Yang, Department of Physics, KAIST||"Visualization of oxygen vacancy in motion and the interplay with electronic conduction"|
|97||Oct. 07 (Fri), 4:00 PM||E6-2. #1323(1st fl.)||Dr. Choong Hyun Kim,IBS-CCES, Seoul National University||“Tilt engineering of 4d and 5d transition metal oxides?”|
|96||Oct. 07 (Fri), 1:30 PM||E6-2. #1323(1st fl.)||Dr. Suk Bum Chung, IBS-CCES , Seoul National University||“Symmetry and topology in transition metal dichalcogenide?”|
|95||2016/09/29-12/13||E6-2, #1323||Sangyoon Han 외||2016 Fall, Physics Seminar Serises|
|94||Sep. 29th(Thu), 4PM||E6-2 #1323 (1st floor)||Dr. Sangyoon Han, Department of Physics, KAIST||Large-scale Silicon Photonic MEMS Switches|
|93||Sep. 29 (Thu), 4:00 PM||E6-2. #2501(2nd fl.)||Dr. Minu Kim, Institute for Basic Science, Seoul National University||Exploring the phase diagram of BaBiO3: epic voyage of just another bad trip?|
|92||Sep. 22, 2016(Thu), 3:30 PM||#1323(E6-2, 1st fl.)||Dr. Haiyang Yan (Institute of Nuclear Physics and Chemistry)||Polarized 3He, Polarized Neutrons and New Interactions beyond the Standard Model|
|91||4pm, Sep. 21 (Wed.||E6-2. #2502(2nd fl.)||Dr. Henrik Johannesson , University of Gothenburg (Sweden) and Beijing Computational Science Research Center (China)||Entanglement probe of two-impurity Kondo physics|
|90||Sep. 22, 2016(Thu), 3:30 PM||#1323(E6-2, 1st fl.)||Dr. Haiyang Yan (Institute of Nuclear Physics and Chemistry)||Polarized 3He, Polarized Neutrons and New Interactions beyond the Standard Model|
|89||2016/09/05-12/12 4PM||Natual Scien Bldg.(E6)m #1501||Yeong Kwan Kim 외||Physics Colloquium : 2016 Fall|
|88||Sep. 02(Fri) 4:00 PM||E6-2(1st fl) #1323||Dr. Yong-Joo Doh, Department of Physics and Photon Science, GIST||Quantum Electrical Transport in Topological Insulator Nanowires|
|87||Sep. 02(Fri) 2:30 PM||E6-2(1st fl.), #1323||Dr. Yong-Hyun Kim,Graduate School of Nanoscience and Technology, KAIST||Nanoscale Thermal Physics: Seebeck Effect and Nanoscale Friction|
|86||Aug. 4, 2016 (Thu.), 2:30 pm||KAIST Natural Science Building (E6-5), EDU 3.0 Room(1st fl.)||Prof. Argyris Nicolaidis||Relational Logic (with applications to Quantum Mechanics, String Theory, Cosmology, Neutrino Oscillations, Statistical Mechanics)|
|85||Jul. 28 (Thu.) 4PM||#1323(E6-2. 1st fl.)||Prof. Johannes Pollanen, Jerry Cowen Chair of Experimental Physics at Michigan State University||Low Dimensional Electrons: On the Road to Hybrid Quantum Systems|
|84||Jul. 08 (Fri.) 2PM||#1323(E6-2. 1st fl.)||Dr. Junhyun Lee, Harvard University||Electronic quasiparticles in the quantum dimer model|