|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||2019/09/18 - 12/5||Seminar Room #1323||Prof. David Schuster and etc.||Fall 2019: Physics Seminar Serises|
|공지||2019/09/02 - 12/09||Seminar Room 1501||이호성 박사 (한국표준과학연구원) and etc.||Fall 2019: Physics Colloquium|
|64||May 31 (Fri.), 11:00 AM||#1323, E6-2||Prof. Guido Burkard||Cavity QED with Spin Qubits|
|63||May 24 (Fri.), 16:00 PM||#1323, E6-2||Prof. Soonjae Moon||Infrared spectroscopy study on metal-insulator transitions in layered perovskite iridates|
|62||May 30 (Thu.), 16:00 PM||#1323, E6-2||Prof. Chang-Hee Cho||Tuning the excitonic properties of semiconductors with light-matter interactions|
|61||November 14 (Thu.), 16:00 PM||#1323, E6-2||Prof. Ji-Hun Kang||Semi-classical model of polariton propagation|
|60||November 28 (Thu.), 16:00 PM||#1323, E6-2||Prof. Kyung Taec Kim||Generation of coherent EUV emissions using ultrashort laser pulses|
|59||December 3 (Tue.), 4:00 PM||#1323, E6-2||Dr. Jong Mok Ok||Toward Quantum Materials with Correlated Oxides|
|58||December 5 (Thu.), 16:00 PM||#1323, E6-2||Prof. Soon-Hong Kwon||Subwavelenth Photonic Devices: From Single Photon Sources to Solar Cell|
|57||June 17 (Mon.), 10:30 AM||#1323, E6-2||Dr. See-Hun Yang||Chiral Spintronics|
|56||June 28 (Fri.), 13:30 PM||#1323, E6-2||Dr. Yusuke Kozuka||Magnetic domains and domain wall conduction in pyrochlore iridate thin films and heterostructures|
|55||July 30 (Tue), 4:00 PM||#1323, E6-2||Dr. Mingu Kang||Dirac fermions and flat bands in correlated kagome metals|
|54||2019. 8. 22 4PM & 8. 23 3PM||#1323, E6-2||Prof. Andrew N Cleland||Physics and Applications in Nanoelectronics and Nonomechanics|
|53||September 18(Wed.), 16:00PM||#1323, E6-2||Prof.David Schuster||Exploring Synthetic Quantum Matter in Superconducting Circuits|
|52||September 26 (Thu.), 16:00 PM||#1323, E6-2||Han Seb Moon||Entanglement Swapping with Autonomous Polarization-Entangled Photon-Pairs from Warm Atomic Ensemble|
|51||October 15 (Tue.), 16:00 PM||#1323, E6-2||Prof. Pilkyung Moon||Moiré superlattices and graphene quasicrystal|
|50||October 17 (Thu.), 16:00 PM||#1323, E6-2||Prof. Namkyoo Park||Top down manipulation of Waves : From Metamaterials, Correlated Disorder, Quantum Analogy, to Digital Processing|
|49||Oct. 25 (Fri), 15:00 ~||#1323, E6-2||Daesu Lee,Junwoo Son,MyungJoon Han ,Siheon Ryee,Eun-Gook Moon||Physics Seminar|
|48||October 29 (Tue.), 14:30 PM||#1323, E6-2||Prof. Jörg Wrachtrup||Quantum sensing|
|47||November 5 (Tue.), 4:00 PM||#1323, E6-2||Dr. Shik Shin||Study on nanomaterials by the development of ultrahigh resolution laser-photoelectron microscopy (PEEM)|
|46||November 7 (Thu.), 16:00 PM||#1323, E6-2||Prof. Je-Hyung Kim||Integrated quantum photonics with solid-state quantum emitters|
|45||Mar. 2nd (Thu), 4:00 p.m||#1323(E6-2. 1st fl.)||Dr. Jonathan Denlinger, Lawrence Berkeley National Lab||“Progress in the comparison of ARPES to DMFT for d and f strongly correlated electron systems”|