To realize good ideas, research environments, techniques, and instruments are important.
We are preparing the best resources to conduct interesting research.
Research environments
We prepare enough working space for group members to conduct their creative works.
We are collaborating with other groups (Univ. Tohoku, RIKEN, Univ. Tokyo, Ruhr Univ. Bochum, UCSB, etc.).
Techniques
We have the following techniques and skills on fabrication and measurements.
Fabrication
Photo and EB lithography: Patterning as small as 10nm
Etching and film formation: Etching of GaAs, InAs, Si, Graphene, h-BN, ..., Film formation with Ti, Au, Co, SiO2, Al2O3, ...
Microscopy with SEM, AFM: Microscopy of nano devices with SEM and AFM
Transfer of 2D materials: Stack and transfer of 2D materials
Cryogenic
Operation and maintenance of fridges: Dry dilution refrigerators (including bottom loading systems), Wet type dilution refrigerators (with 1K pods/ JT valves), 1K pod fridges, Pulse tube coolers, ...
Operation and maintenance of superconducting magnet: Superconducting magnet up to 15T
Handling of cryogen: Liquid nitrogen, helium
Fabrication of fridges and superconducting magnets: 1K pod fridges, 4K test inserts, 4T superconducting magnet, Machining with lathes, milling machines, electric discharge machines, ..., Brazing
Measurement
Low noise measurement in low temperature: Measurement of currents and voltages in the order of fA and nV in cryogenic temperature, Signal extraction using lock-in amplifiers, ...
High frequency technique: Handling of high frequency lines in cryogenic temperature, Measurements with microwave up to 40GHz, High speed measurements with RF reflectometry
Fabrication of electronic instruments and facilities: Low noise instruments, Cryogenic high frequency components (amplifiers, bias tees, ...), RF circuits
Programming
Automation of measurement and analysis: Automation with Python, Igor and LabView
CAD: Design of devices, instruments and labs with CAD
FPGA: High-speed electronics utilizing FPGA
Device simulation: Fabrication of measurement instruments with microcomputers
Instruments
We have instruments for device fabrications and measurements.
Device fabrication:
We are fabricating nanodevices utilizing equipment in Tohoku University and RIKEN.
Cryogenic:
We have cryogenic instruments to realize ultra-low temperatures required for observing quantum effects.
In collaboration with RIKEN team, we can also access the large cryogenic systems.
Measurement:
We have measurement instruments to control and detect local electronic states in nanostructures.
We are also developing original low-noise and high-speed measurement instruments.
