146 citations · 1.4k across the 45 of their papers we have counts for
45 papers
Theoretical studies on quantum imaging with time-integrated single-photon detection under realistic experimental conditions
Byeong-Yoon Go, Changhyoup Lee, Kwang-Geol Lee
We study a quantum-enhanced differential measurement scheme that uses quantum probes and single-photon detectors to measure a minute defect in the absorption parameter of an analyt…
Quantum illumination with non-Gaussian states: Bounds on the minimum error probability using quantum Fisher information
Changsuk Noh, Changhyoup Lee, Su-Yong Lee
Quantum illumination employs entangled states to detect a weakly reflective target in a thermal bath. The performance of a given entangled state is evaluated from the minimum error…
Distributed quantum phase sensing for arbitrary positive and negative weights
Changhun Oh, Liang Jiang, Changhyoup Lee
Estimation of a global parameter defined as a weighted linear combination of unknown multiple parameters can be enhanced by using quantum resources. Advantageous quantum strategies…
Quantum Plasmonic Sensors
Changhyoup Lee, Benjamin Lawrie, Raphael Pooser +3
The extraordinary sensitivity of plasmonic sensors is well known in the optics and photonics community. These sensors exploit simultaneously the enhancement and the localization of…
Optimal circular dichroism sensing with quantum light: Multi-parameter estimation approach
Christina Ioannou, Ranjith Nair, Ivan Fernandez-Corbaton +3
The measurement of circular dichroism (CD) has widely been exploited to distinguish the different enantiomers of chiral structures. It has been applied to natural materials (e.g. m…
Experimental quantum polarimetry using heralded single photons
Seung-Jin Yoon, Joong-Sung Lee, Carsten Rockstuhl +2
We perform experimental quantum polarimetry using a heralded single photon to analyze the optical activity of linearly polarized light traversing a chiral medium. Three kinds of es…
Optimal Distributed quantum sensing using Gaussian states
Changhun Oh, Changhyoup Lee, Seok Hyung Lie +1
We find and investigate the optimal scheme of quantum distributed Gaussian sensing for estimation of the average of independent phase shifts. We show that the ultimate sensitivity…
Superconducting nanowire single-photon spectrometer exploiting cascaded photonic crystal cavities
Youngsun Yun, Andreas Vetter, Robin Stegmueller +4
Superconducting nanowire single-photon detectors promise efficient (~100%) and fast (~Gcps) detection of light at the single-photon level. They constitute one of the building block…
Using states with a large photon number variance to increase quantum Fisher information in single-mode phase estimation
Changhyoup Lee, Changhun Oh, Hyunseok Jeong +2
When estimating the phase of a single mode, the quantum Fisher information for a pure probe state is proportional to the photon number variance of the probe state. In this work, we…
Optimal measurements for quantum fidelity between Gaussian states and its relevance to quantum metrology
Changhun Oh, Changhyoup Lee, Leonardo Banchi +3
Quantum fidelity is a measure to quantify the closeness of two quantum states. In an operational sense, it is defined as the minimal overlap between the probability distributions o…
Quantum plasmonic sensing using single photons
Joong-Sung Lee, Seung-Jin Yoon, Hyungju Rah +5
Reducing the noise below the shot-noise limit in sensing devices is one of the key promises of quantum technologies. Here, we study quantum plasmonic sensing based on an attenuated…
Optimal Gaussian measurements for phase estimation in single-mode Gaussian metrology
Changhun Oh, Changhyoup Lee, Carsten Rockstuhl +4
The central issue in quantum parameter estimation is to find out the optimal measurement setup that leads to the ultimate lower bound of an estimation error. We address here a ques…
Quantum plasmonic N00N state in a silver nanowire and its use for quantum sensing
Yang Chen, Changhyoup Lee, Liu Lu +9
The control of quantum states of light at the nanoscale has become possible in recent years with the use of plasmonics. Here, many types of nanophotonic devices and applications ha…
Effective Formalism for Open Quantum System Dynamics: Time-coarse-graining Approach
Chang-Woo Lee, Changsuk Noh, Jaewan Kim
We formulate an effective-description framework for the dynamics of open quantum systems by extending the time-coarse-graining formalism to open systems. Our coarse-graining proced…
Experimental demonstration of quantum learning speed-up with classical input data
Joong-Sung Lee, Jeongho Bang, Sunghyuk Hong +4
We consider quantum-classical hybrid machine learning in which large-scale input channels remain classical and small-scale working channels process quantum operations conditioned o…
Quantum noise reduction in intensity-sensitive surface plasmon resonance sensors
Joong-Sung Lee, Trung Huynh, Su-Yong Lee +5
We investigate the use of twin-mode quantum states of light with symmetric statistical features in their photon number for improving intensity-sensitive surface plasmon resonance (…
Sub-Poisson-Binomial Light
Changhyoup Lee, Simone Ferrari, Wolfram H. P. Pernice +1
We introduce the general parameter Q_PB that provides an experimentally accessible nonclassicality measure for light. The parameter is quantified by the click statistics obtained f…
Duality in entanglement of macroscopic states of light
Su-Yong Lee, Chang-Woo Lee, Pawel Kurzynski +2
We investigate duality in entanglement of a bipartite multi-photon system generated from a coherent state of light. The system can exhibit polarization entanglement if the two part…
Quantifiable simulation of quantum computation beyond stochastic ensemble computation
Jeongho Bang, Junghee Ryu, Chang-Woo Lee +3
In this study, a distinctive feature of quantum computation (QC) is characterized. To this end, a seemingly-powerful classical computing model, called "stochastic ensemble machine…
Quantum plasmonic sensing: beyond the shot-noise and diffraction limit
Changhyoup Lee, Frederik Dieleman, Jinhyoung Lee +3
Photonic sensors have many applications in a range of physical settings, from measuring mechanical pressure in manufacturing to detecting protein concentration in biomedical sample…
Quantum walk as a simulator of nonlinear dynamics: Nonlinear Dirac equation and solitons
Chang-Woo Lee, Paweł Kurzyński, Hyunchul Nha
Quantum walk (QW) provides a versatile tool to study fundamental physics and also to make a variety of practical applications. We here start with the recent idea of {\it nonlinear}…
Quantum macroscopicity measure for arbitrary spin systems and its application to quantum phase transitions
Chae-Yeun Park, Minsu Kang, Chang-Woo Lee +3
We explore a previously unknown connection between two important problems in physics, i.e., quantum macroscopicity and the quantum phase transition. We devise a general and computa…
Quantum phase estimation using path-symmetric entangled states
Su-Yong Lee, Chang-Woo Lee, Jaehak Lee +1
We study the sensitivity of phase estimation using a generic class of path-symmetric entangled states , where an arbitrary state …
Quantum plasmonic excitation in graphene and robust-to-loss propagation
George W. Hanson, S. A. Hassani Gangaraj, Changhyoup Lee +2
We investigate the excitation of quantum plasmonic states of light in graphene using end-fire and prism coupling. In order to model the excitation process quantum mechanically we q…