30 citations · 152 across the 26 of their papers we have counts for
27 papers · 1 filter
Phase-Flag Access and No-Go Constraints on Quotient-Space Real Quantum Mechanics
Jeongho Bang, Kyoungho Cho, Kyunghyun Baek
Barrios Hita et al. [Phys. Rev. Lett. 136, 240202 (2026)] proposed a quotient-space formulation of quantum mechanics over the real numbers and concluded that complex numbers are on…
Hidden Complex Structure in Quotient-Space Real Quantum Mechanics
Jeongho Bang, Kyoungho Cho, Kyunghyun Baek
Barrios Hita et al. [Phys. Rev. Lett. , 240202 (2026)] argued that quantum mechanics can be formulated over the real numbers by replacing the tensor-product postulate wit…
Maximal coherence of quantum measurement and the resource theory of sharpness
Kyunghyun Baek, Yonggi Jo, Hyunchul Nha
A resource theory of quantum measurement can be addressed in terms of quantum coherence and measurement sharpness, respectively. The former analyzes the off-diagonal structure of P…
First-Quantized Relativistic Quantum Simulation with Periodic and Dirichlet Boundary Conditions
Jeongho Bang, Timothy P. Spiller, Kyunghyun Baek +2
In this work, we present a methodology for first-quantized relativistic quantum simulation on one-dimensional finite domains under the two boundary conditions most commonly used in…
Finite Imaginary-Time Evolution for Polynomial Unconstrained Binary Optimization
Jaehee Kim, Juhyeon Kim, Gwonhak Lee +4
Imaginary-time evolution is a standard primitive for ground-state preparation but is nonunitary, precluding direct quantum implementation. We develop Finite Imaginary-Time Evolutio…
Quantum Amplitude-Amplification Eigensolver: A State-Learning-Assisted Approach beyond Energy-Gradient-Based Heuristics
Kyunghyun Baek, Seungjin Lee, Joonsuk Huh +4
Ground-state estimation lies at the heart of a broad range of quantum simulations. Most near-term approaches are cast as variational energy minimization and thus inherit the challe…
Relativistic Quantum Simulation under Periodic and Dirichlet Boundary Conditions: A First-Quantised Framework for Near-Term Devices
Jaewoo Joo, Timothy P. Spiller, Kyunghyun Baek +1
We present a new recipe for relativistic quantum simulation using the first quantisation approach, under periodic (PBC) and Dirichlet (DBC) boundary conditions. The wavefunction is…
Subspace Variational Quantum Simulation: Fidelity Lower Bounds as Measures of Training Success
Seung Park, Dongkeun Lee, Jeongho Bang +2
We propose an iterative variational quantum algorithm to simulate the time evolution of arbitrary initial states within a given subspace. The algorithm compresses the Trotter circu…
Quantum Simulation of Dynamical Transition Rates in Open Quantum Systems
Robson Christie, Kyunghyun Baek, Jeongho Bang +1
Estimating transition rates in open quantum systems is hampered by computing-resource demands that grow rapidly with system size. We present a quantum-simulation framework that ena…
Quantum superposing algorithm for quantum encoding
Jaehee Kim, Taewan Kim, Kyunghyun Baek +3
Efficient encoding of classical data into quantum state -- currently referred to as quantum encoding -- holds crucial significance in quantum computation. For finite-size databases…
Global optimization in variational quantum algorithms via dynamic tunneling method
Seung Park, Kyunghyun Baek, Seungjin Lee +1
We present a global optimization routine for the variational quantum algorithms, which utilizes the dynamic tunneling flow. Originally designed to leverage information gathered by…
Resource-compact time-optimal quantum computation
Taewan Kim, Kyunghyun Baek, Yongsoo Hwang +1
Fault-tolerant quantum computation enables reliable quantum computation but incurs a significant overhead from both time and resource perspectives. To reduce computation time, Aust…
Robustness measures for quantifying nonlocality
Kyunghyun Baek, Junghee Ryu, Jinhyoung Lee
We suggest generalized robustness for quantifying nonlocality and derive its equivalence to the maximum violation ratio of Bell inequalities defined as vectors with non-negative el…
Generalized Euler angles for a unitary control of the Hamiltonian system
Seungjin Lee, Kyunghyun Baek, Jeongho Bang
We provide an angular parametrization of the special unitary group generalizing Euler angles for by successively applying the KAK decompositio…
Variational quantum state discriminator for supervised machine learning
Dongkeun Lee, Kyunghyun Baek, Joonsuk Huh +1
Quantum state discrimination (QSD) is a fundamental task in quantum information processing with numerous applications. We present a variational quantum algorithm that performs the…
-depth-optimized Quantum Search with Quantum Data-access Machine
Jung Jun Park, Kyunghyun Baek, M. S. Kim +3
Quantum search algorithms offer a remarkable advantage of quadratic reduction in query complexity using quantum superposition principle. However, how an actual architecture may acc…
Quantifying non-Gaussianity of a quantum state by the negative entropy of quadrature distributions
Jiyong Park, Jaehak Lee, Kyunghyun Baek +1
We propose a non-Gaussianity measure of a multimode quantum state based on the negentropy of quadrature distributions. Our measure satisfies desirable properties as a non-Gaussiani…
Fundamental limits on concentrating and preserving tensorized quantum resources
Jaehak Lee, Kyunghyun Baek, Jiyong Park +2
Quantum technology offers great advantages in many applications by exploiting quantum resources like nonclassicality, coherence, and entanglement. In practice, an environmental noi…
Average fidelity and fidelity deviation in noisy quantum teleportation
WooYeong Song, Junghee Ryu, Kyunghyun Baek +1
We analyze the average fidelity (say, F) and the fidelity deviation (say, D) in noisy-channel quantum teleportation. Here, F represents how well teleportation is performed on avera…
Quantifying coherence of quantum measurements
Kyunghyun Baek, Adel Sohbi, Jaehak Lee +2
In this work we investigate how to quantify the coherence of quantum measurements. First, we establish a resource theoretical framework to address the coherence of measurement and…
Entropic Uncertainty Relations via Direct-Sum Majorization Relation for Generalized Measurements
Kyunghyun Baek, Hyunchul Nha, Wonmin Son
We derive an entropic uncertainty relation for generalized positive-operator-valued measure (POVM) measurements via a direct-sum majorization relation using Schur concavity of entr…
Necessary and sufficient condition for joint measurability
Jeongwoo Jae, Kyunghyun Baek, Junghee Ryu +1
In order to analyze joint measurability of given measurements, we introduce a Hermitian operator-valued measure, called -measure, such that it has marginals of positive operator…
Non-Gaussianity and entropy-bounded uncertainty relations: Application to detection of non-Gaussian entangled states
Kyunghyun Baek, Hyunchul Nha
We suggest an improved version of Robertson-Schrödinger uncertainty relation for canonically conjugate variables by taking into account a pair of characteristics of states: non-Gau…
Faithful measure of Quantum non-Gaussianity via quantum relative entropy
Jiyong Park, Jaehak Lee, Kyunghyun Baek +2
We introduce a measure of quantum non-Gaussianity (QNG) for those quantum states not accessible by a mixture of Gaussian states in terms of quantum relative entropy. Specifically,…