Equipments

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.