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 each 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 fabrications and measurements.

ClassificationTechniqueExperience
FabricationPhoto and EB lithographyPatterning as small as 10nm
 Etching
Film formation
Etching of GaAs, InAs, Si ...
Film formation with Ti, Au, Co, SiO2, Al2O3, ...
 Microscopy with SEM, AFMMicroscopy of nano devices with SEM and AFM
CryogenicOperation and maintenance of fridgesWet type dilution refrigerators (with 1K pods/ JT valves), Dry dilution refrigerators (including bottom loading systems), 1K pod fridges, Pulse tube coolers, ...
 Operation of superconducting magnetSuperconducting magnet up to 15T
 Handling of cryogenLiquid nitrogen, helium
 Fabrication of fridges and superconducting magnets1K pod fridges, 4K test inserts, 4T superconducting magnet
Machining with lathes, milling machines, electric discharge machines, ..., Brazing
MeasurementLow noise measurement in low temperatureMeasurement of currents and voltages in the order of fA and nV in cryogenic temperature
Signal extraction using lock-in amplifiers, ...
 High frequency techniqueHandling of high frequency lines in cryogenic temperature
Measurements with microwave up to 40GHz
High speed measurements with RF reflectometry
 Fabrication of electronic instruments and facilitiesLow noise instruments
Cryogenic high frequency components (amplifiers, bias tees, ...)
RF circuits
ProgrammingAutomation of measurementAutomation with Python, Igor and LabView
 AnalysisAutomation of analysis with Python and Igor
 CADDesign of devices, instruments and labs with Shapr3D, Vectorworks and AutoCAD
 Device simulation3D analysis of semiconductor devices with 3D Poisson-Schrödinger solver
 MicrocomputerFabrication of measurement instruments with AVR


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.