Fabrication of (Bi)(BiTe) superlattice films by Te desorption from a pristine BiTe film

Kusaka, Shotaro*; Sasaki, Taisuke*; Sumida, Kazuki; Ichinokura, Satoru*; Ideta, Shinichiro*; Tanaka, Kiyohisa*; Hono, Kazuhiro*; Hirahara, Toru*

Applied Physics Letters, 120(17), p.173102_1 - 173102_5, 2022/04

https://doi.org/10.1063/5.0090207

Magnetization energy current in the axial magnetic effect

Shitade, Atsuo*; Araki, Yasufumi

Physical Review B, 103(15), p.155202_1 - 155202_8, 2021/04

https://doi.org/10.1103/PhysRevB.103.155202

The axial magnetic effect (AME) is one of the anomalous transport phenomena in which the energy current is induced by an axial magnetic field. Here we numerically study the AME for the relativistic Wilson fermion in the axial magnetic field and a twisted Dirac semimetal. The AME current density inside the bulk is nonzero, and particularly in the low energy regime for the former model, it is explained by the field-theoretical results without any fitting parameter. However, for both models, the average AME current density vanishes owing to the surface contribution. The axial gauge field is regarded as the spatially modulated (effective) Zeeman field and induces the spatially modulated energy magnetization. The AME is attributed to the magnetization energy current and hence cannot be observed in transport experiments.

Simultaneous measurements of superradiance at multiple wavelength from helium excited states, 2; Analysis

Ohae, Chiaki*; Harries, J.; Iwayama, Hiroshi*; Kawaguchi, Kentaro*; Kuma, Susumu*; Miyamoto, Yuki*; Nagasono, Mitsuru*; Nakajima, Kyo*; Nakano, Itsuo*; Shigemasa, Eiji*; et al.

Journal of the Physical Society of Japan, 85(3), p.034301_1 - 034301_10, 2016/03

https://doi.org/10.7566/JPSJ.85.034301

Transient charge dynamics in argon-cluster nanoplasmas created by intense extreme-ultraviolet free-electron-laser irradiation

Iwayama, Hiroshi*; Harries, J.; Shigemasa, Eiji*

Physical Review A, 91(2), p.021402_1 - 021402_5, 2015/02

https://doi.org/10.1103/PhysRevA.91.021402

Superfluorescence observed using an EUV-FEL

Harries, J.; Shigemasa, Eiji*

Hoshako, 26(6), p.327 - 334, 2013/11

https://cir.nii.ac.jp/crid/1571980076090617728

We report on the first observation of superfluorescence (collective spontaneous emission) at an FEL, using the EUV free-electron laser and a high number density helium gas cell. We introduce superfluorescence as an example of quantum optics experiments which can be performed at the new generation of light sources, and discuss future prospects, including the extension to shorter wavelengths.

Towards coherent control of SASE pulses using propagation through helium gas at wavelengths corresponding to double excitation

Harries, J.; Nagasono, Mitsuru*; Iwayama, Hiroshi*; Shigemasa, Eiji*

Journal of Physics B; Atomic, Molecular and Optical Physics, 46(16), p.164021_1 - 164021_5, 2013/08

https://doi.org/10.1088/0953-4075/46/16/164021

Terahertz tomography of a photo-induced carrier based on pump-probe spectroscopy using counterpropagation geometry

Tsubouchi, Masaaki; Nagai, Masaya*; Oshima, Yasuhiro*

Optics Letters, 37(17), p.3528 - 3530, 2012/09

https://doi.org/10.1364/OL.37.003528

A novel technique for the terahertz (THz) tomography of a photo-induced carrier that is based on optical-pump THz-probe time-resolved reflection spectroscopy using counter-propagation geometry of the pump and probe pulses has been proposed. Transient reflection due to the photo-induced carrier provides information about the physical properties and spatial distribution separately. We have experimentally demonstrated this method using a silicon wafer. The obtained complex reflection can be reproduced by the exact solution of Maxwell's equations, assuming an exponential distribution of the photo-induced carrier density.

Design and manufacture of synchrotron radiation beamline for high speed etching with XeF

Nakai, Tadafumi*; Uno, Hidetaka*; Zhang, Z.*; Tero, Ryogo*; Suzui, Koichi*; Teraoka, Yuden; Yoshigoe, Akitaka; Makinura, Tetsuya*; Murakami, Koichi*; Urisu, Tsuneo*

no journal, , 

A synchrotron radiation beamline has been designed and manufactured at UVSOR facilities in Institute for Molecular Science to achieve high speed etching of Si by simultaneous irradiation of white synchrotron radiation and XeF molecules. A previously-found beamline was modified by a differential pumping system. A new experimental apparatus was manufactured. In that apparatus, a silicon wafer, exposed to XeF molecules sublimated from the solid, was irradiated by the white synchrotron radiation to be etched with a high speed. This high speed etching phenomenon is due to desorption of silicon fluorides formed by a surface reaction of silicon and fluorin atoms from the XeF molecules.

Ultrafast optical pump - THz probe time-resolved spectroscopy on Si

Tsubouchi, Masaaki; Yokoyama, Atsushi; Nagai, Masaya*; Oshima, Yasuhiro*

no journal, , 

no abstracts in English

Observation of superfluorescence following extreme ultraviolet free-electron laser excitation

Nagasono, Mitsuru*; Harries, J.; Iwayama, Hiroshi*; Tono, Kensuke*; Togashi, Tadashi*; Semba, Yasunori*; Ohashi, Haruhiko*; Yabashi, Makina*; Ishikawa, Tetsuya*; Shigemasa, Eiji*

no journal, , 

no abstracts in English