Dr Tsung-Yeh Yang

Research Interests

• Quantum Information
• Spintronics

Tsung-Yeh Yang received his B.S. and M.S. in materials science from National Tsing-Hau University (Taiwan) in 2004 and 2006, respectively. He then moved to Aachen (Germany) to do a PhD at RWTH Aachen University. After the completion of PhD, he worked as a postdoc at Academia Sinica (Taiwan) from 2011 to 2012. In October 2012, he joined Hitachi Cambridge Laboratory. His research interests have included spin injection/detection in graphene-based devices and charge transport in graphene devices. He currently works on quantum information technology.

Recent research highlights:

• Spin transport in graphene devices:
  
  

  Graphene has been considered as a promising material for spintronic applications due to its weak spin-orbit coupling and negligible hyperfine interaction. Therefore, spin transport in graphene has become an interesting topic in the recent years. The simplest and most convenient approach to study the spin dynamics in materials is to fabricate spin-valve structures and measure the spin relaxation behaviors. In this work, graphene non-local spin-valve devices are fabricated on Si/SiO₂ substrate. Spin polarized current is injected from a ferromagnetic electrode (injector) into graphene via a thin MgO barrier. The spin signal is detected at the ferromagnetic detector electrode. The spin relaxation times can be then extracted by performing spin precession experiments, and the relevant spin relaxation mechanism can be determined. This study is essential for improving the spin life time in graphene in order to enhance the spintronic device performance.

• Charge transport in graphene device:
  
  

  Graphene's high charge carrier mobility at room temperature makes it very potential for next generation electronic device applications. The first graphene transistor was fabricated on conventional Si/SiO₂ substrate. However, the mobility can be limited due to the Si/SiO₂ substrate, e.g. the surface roughness of SiO₂ and charge-impurities. Therefore, an alternative and more ideal substrate, h-BN, has been used due to its smoother surface and lower density of charged-impurity. In this work, graphene devices are fabricated on Si/SiO₂/h-BN substrate. The experiments show that the carrier mobilities in this sort of graphene devices are indeed improved, which are helpful for future technology.

Recent Research projects

Quantum information processing: Based on current industrial Si-based manufacturing process, we use highly doped silicon isolated double quantum dots (IDQDs) as quantum bits (qubits). By applying gate bias, we are able to manipulate the states of qubits and further operate logic computing.

Last Publications

• Y. Peng, A. Ruffino, T. -Y. Yang, J. Michniewicz, M. F. Gonzalez-Zalba, and E. Charbon, Ieee Journal Of Solid-state Circuits 57, 8, (2022), A Cryo-CMOS Wideband Quadrature Receiver With Frequency Synthesizer for Scalable Multiplexed Readout of Silicon Spin Qubits

• T. -Y. Yang, A. Ruffino, J. Michniewicz, Y. Peng, E. Charbon, and M. F. Gonzalez-Zalba, Ieee Elec. Dev. Lett. 101, 981 (2020), Quantum Transport in 40-nm MOSFETs at Deep-Cryogenic Temperatures

• L. Hutin, B. Bertrand, E. Chanrion, H. Bohuslavskyi, F. Ansaloni, T. -Y. Yang, J. Michniewicz, D. J. Niegemann, C. Spence, T. Lundberg, A. Chatterjee, A. Crippa, J. Li, R. Maurand, R. Jehl, M. Sanquer, M. F. Gonzalez-Zalba, F. Kuemmeth, Y. M. Niquet, S. De Franceschi, M. Urdampilleta, T. Meunier, and M. Vinet, Tech. Digest Of IEEE International Electron Devices Meeting (IEDM), p1 (2020), Gate reflectometry for probing charge and spin states in linear Si MOS split-gate arrays