Speaker: Prof. Yoon-Ho Kim
University: Pohang University of Science and Technology
Emcee：Prof. Jietai Jing
Time：14:00pm, 28th October, 2022
Place：Optics Building B325
ZOOM Conference ID: 82773432175
ZOOM Conference Password:123456
Link: https://us06web.zoom.us/j/82773432175?pwd=SFJ2bnBpbjN4QmtlV0RiOEt1QjVEQT09
About the Speaker:
Yoon-Ho Kim is Professor of Physics at Pohang University of Science and Technology from 2015. He received his B.S. in Physics from Yeungnam University, Korea in 1995. He received his Ph.D. in Applied Physics from University of Maryland in 2001. From 2001 to 2004, he successively served as a postdoctoral Research Associate and Eugene P. Wigner Fellow at the Oak Ridge National Laboratory, USA. From 2004 to 2015, he successively served as an assistant professor and associate professor of Physics at Pohang University of Science and Technology. His main research focus on three areas. The first is quantum information about generalized quantum measurement, quantum metrology, quantum tomography, multi-qubit entanglement, decoherence, and quantum communication. The second is atom-photon coherent interaction about atomic quantum light sources, stationary photons in an atomic medium, atomic quantum memory and photon-photon interaction. The third is quantum interferometry and imaging with entangled photons.
Abstract：
Quantum information protocols are being deployed in increasingly practical scenarios, via optical fibers or free space, alongside classical communication channels. For long-distance quantum communication protocols, the distribution of entanglement through noisy quantum channels remains a critical unsolved gap. Indeed, entanglement is very fragile to noise-induced degradation, so that even a perfectly-prepared entangled state quickly degrades to a partially mixed state, where quantum operation ceases to be possible; and, the presence of noise within the quantum transmission channels is nearly unavoidable as it can come from stray light, crosstalk or linear/nonlinear effects in the transmission medium. Recent years have witnessed tremendous efforts for noise suppression within transmission channels or proposals to switch to quantum protocols to high-dimension entangled states to attenuate this issue.
Here, instead, we show that hyper-entanglement, the property of quantum states that are simultaneously entangled in several degrees of freedom, can be effectively employed to protect entanglement distribution from noisy transmission channels. Our strategy does not require changing the intrinsic quantum communication protocol under exam: instead, we take advantage of the fundamental property of hyperentanglement, i.e. the additional quantum correlation in a different space, to discriminate “signal” photons, i.e. the entangled photons endowed with such correlation, from “noise” photons coming from other sources.
