Quantum Computation

Quantum registers with diamond NV centers: Quantum registers are an important component of quantum computers as a set of qubits that can be read after quantum calculations by selectively manipulating quantum states. We study solid state system for the quantum registers using 13C nuclear spins located near a single NV center of diamond. We plan to realize quantum algorithms, quantum error correction, and large-scale multi-qubit quantum networks using tens of solid-state spin qubits quantum resister.

Spin-photon quantum interface: Color defects such as NV center in diamond have a great potential for a suitable quantum node. With strong advantages on the interaction with photon, the spin-photon interface in diamond is one of the promising candidates. We study the control of the interaction between spin and photon in the NV center system, planning to create spin-photon entanglement and distributed spin-spin entanglement via photon. This spin-photon interface is a key technology for quantum communications to distributed sensing and large-scale cloud quantum computing.

Photonic quantum simulation: It is of importance to find useful applications of near-term quantum processors. KIST efforts in this research direction include, but not limited to, quantum computational chemistry and quantum machine learning. In order to take advantages of non-ideal quantum information processors, we focus on the quantum-classical hybrid architecture.

Publication

D. Lee et al., “Error-mitigated photonic variational quantum eigensolvers using a single-photon ququart”, Optica 9, 88 (2022).
I. Kim et al., “Implementation of a 3 × 3 directionally-unbiased linear optical multiport", Opt. Express 19, 29527 (2021).
S. W. Jeon et al., “Bright nitrogen-vacancy centers in diamond inverted nanocones,” Acs Photon. 7, 2739-2747 (2020).