This is a seminar jointly organized by the three groups working on quantum physics and technology at Department of Physics, Kindai University, namely Condensed-Matter Theory (CMT), Quantum Control (QC), and QMB Laboratories.

Scheduled talks

Fiscal year 2025

Time and date: 10:45-, April 9, 2025

Room: Simulation and Experiment Room, 3rd Floor, 31 East Bldg. + Webcast via Zoom

Speaker: Furuchi, Rito (QMB)

Title: Theoretical study of frustrated quantum spin systems with exact diagonalization

Abstract: We study frustrated antiferromagnets using the exact diagonalization method. The type of frustration addressed in this research occurs in localized spin systems, such as those represented in half-filled Mott insulators. This frustration occurs when antiferromagnetic interactions construct networks with odd-gons as local structures, causing a variety of exotic phenomena. Extensive studies have been reported on the triangular lattice[1] and the kagome lattice[2] as typical frustrated systems. The Heisenberg model describes such localized spin systems.

Computational approaches such as the quantum Monte Carlo (QMC) method and the density matrix renormalization group (DMRG) method are effective methods to study the Heisenberg model. However, the QMC method suffers from the negative sign problem in frustrated systems, while DMRG faces challenges in interpreting results for systems with two or more spatial dimensions. To avoid these problems, we employ the exact diagonalization method, which, although restricted to systems with a small number of spins, can calculate frustrated system.

In this seminar, we will introduce the methodology of our study, referencing results from our previous work. Specifically, we will present our discovery and analysis of novel magnetization jump phenomena in the floret pentagonal lattice[3], and the third type of ferrimagnetic collapse observed in the Lieb lattice[4]. These phenomena will be discussed in detail.
 
参考文献
[1] O. A. Starykh. Rep. Prog. Phys. 78, 052502 (2015).
[2] P. Mendels and F. Bert. J. Phys. Soc. Jpn. 79, 011001 (2010).
[3] R. Furuchi, H. Nakano, and T. Sakai. J. Phys. Commun. 5, 125008 (2021).
[4] R. Furuchi, H. Nakano, and T. Sakai. J. Phys. Soc. Jpn. 93, 115002 (2024).

Time and date: 10:45-, April 16, 2025

Room: Simulation and Experiment Room, 3rd Floor, 31 East Bldg. + Webcast via Zoom

Speaker:  Yoshida, Takaharu (Tokyo University of Science)

Title: TBA

Abstract: TBA


Time and date: 10:45-, April 23, 2025

Room: Simulation and Experiment Room, 3rd Floor, 31 East Bldg. + Webcast via Zoom

Speaker: Pelayo, Jose Carlos (QMB)

Title: TBA

Abstract: TBA


Time and date: 10:45-, April 30, 2025

Room: Simulation and Experiment Room, 3rd Floor, 31 East Bldg. + Webcast via Zoom

Speaker: Tanaka, Airi (CMT)

Title: TBA

Abstract: TBA


Time and date: 10:45-, May 14, 2025

Room: Simulation and Experiment Room, 3rd Floor, 31 East Bldg. + Webcast via Zoom

Speaker: Yabuuchi, Yoshihiro (QMB)

Title: TBA

Abstract: TBA


Time and date: 10:45-, May 21, 2025

Room: Simulation and Experiment Room, 3rd Floor, 31 East Bldg. + Webcast via Zoom

Speaker: Sidharth Rammohan (QMB)

Title: TBA

Abstract: TBA


Time and date: 10:45-, May 28, 2025

Room: Simulation and Experiment Room, 3rd Floor, 31 East Bldg. + Webcast via Zoom

Speaker: Danshita, Ippei (QMB)

Title: TBA

Abstract: TBA


Time and date: 10:45-, June 4, 2025

Room: Simulation and Experiment Room, 3rd Floor, 31 East Bldg. + Webcast via Zoom

Speaker: Kasamatsu, Kenichi (CMT)

Title: TBA

Abstract: TBA


Time and date: 10:45-, June 11, 2025

Room: Simulation and Experiment Room, 3rd Floor, 31 East Bldg. + Webcast via Zoom

Speaker: Kondo, Yasushi (QC)

Title: TBA

Abstract: TBA


Time and date: 10:45-, June 18, 2025

Room: Simulation and Experiment Room, 3rd Floor, 31 East Bldg. + Webcast via Zoom

Speaker: Ueda, Kenta (QMB)

Title: TBA

Abstract: TBA


Time and date: 10:45-, June 25, 2025

Room: Simulation and Experiment Room, 3rd Floor, 31 East Bldg. + Webcast via Zoom

Speaker: TBA

Title: TBA

Abstract: TBA


Time and date: 10:45-, July 2, 2025

Room: Simulation and Experiment Room, 3rd Floor, 31 East Bldg. + Webcast via Zoom

Speaker: TBA

Title: TBA

Abstract: TBA


Time and date: 10:45-, July 9, 2025

Room: Simulation and Experiment Room, 3rd Floor, 31 East Bldg. + Webcast via Zoom

Speaker: Yuri, Takumi (Osaka Univ.)

Title: TBA

Abstract: TBA


Time and date: 10:45-, July 16, 2025

Room: Simulation and Experiment Room, 3rd Floor, 31 East Bldg. + Webcast via Zoom

Speaker: TBA

Title: TBA

Abstract: TBA


Time and date: 10:45-, July 23, 2025

Room: Simulation and Experiment Room, 3rd Floor, 31 East Bldg. + Webcast via Zoom

Speaker: TBA

Title: TBA

Abstract: TBA

Seminars in the past


Fiscal year 2024

Fiscal year 2023

Fiscal year 2022

Fiscal year 2021

Fiscal year 2020

Fiscal year 2019