Browsing by Author "Hsu, Shih-Ying"

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Current Developments for Taiwanese Women in Physics
(2015)
Hsu, Shih-Ying
;
Ho, Mon-Shu
;
Lin, Jauyn Grace
;
Hu, Shu-Fen
;
Chiu, Ya-Ping
Statistics for 2002 to 2012 show that the percentage of women among graduates in physics and astronomy has not changed much in the Republic of China in Taiwan. Women comprise about 15% of graduates with bachelor\'s degrees in physics and astronomy, 17% of those with master\'s degrees, and 12% of doctorates. The number of female faculty members has increased slightly during this time frame but overall has stayed at approximately 11%.
Nanocrystal shape and nanojunction effects on electron transport in nanocrystal-assembled bulks
(2013)
Chiu, Shao-Chien
;
Jhang, Jia-Sin
;
Lin, Yen-Fu
;
Hsu, Shih-Ying
;
Fang, Jiye
Bulk nanostructured materials are made from the assembly of octahedral PbSe nanocrystals. After thermal annealing, the artificial bulk demonstrates a large difference in behavior depending on the temperature, and a large variation of room-temperature resistivity of up to seven orders of magnitude. This variation originates from the high-indexed sharp edges of the octahedral nanocrystals. As the nanocrystals are arranged in the edge-to-edge configuration, which was observed in scanning electron microscopy images, the inter-nanocrystal capacitance is small due to the small parallel area between the nanocrystals. The small capacitance results in a high thermal fluctuation voltage and drives electron transport. The temperature-dependent resistivity and the electric field-dependent current are highly in agreement with the model of fluctuation-induced tunneling conduction. Thermal annealing reduces the inter-nanocrystal separation distance, creating a large variation in the electrical properties. Specifically, octahedral-shaped PbSe nanocrystals are employed in tailoring the electron transport in bulk nanostructured materials.
Probing into the metal-graphene interface by electron transport measurements
(2013-01-21)
Lin, Yen-Fu
;
Wang, Sheng-Tsung
;
Pao, Chia-Chen
;
Li, Ya-Chi
;
Lai, Cheng-Chieh
Metal-graphene contact recently attracts much attention because of its effects on the performance and the operational speed of graphene field-effect transistor. Simple two-probe graphene devices on mechanically exfoliated graphene flakes are fabricated and the temperature behavior of resistance is measured from room temperature down to liquid helium temperature for the study of electron transport in the interface. Comparing experimental data with several different transport theories, it is confirmed that the model of fluctuation-induced tunneling conduction describes precisely the electron transport and indicates the existence of a thin insulating layer in the metal-graphene interface. Through the interface probing by electron transport measurements, the way to reduce the contact resistance is suggested. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4789554]
Time Dependent Electric Fields Generated DC Currents in a Large Gate-Defined Open Dot
(2010-11-01)
Liu, Kai-Ming
;
Umansky, Vladimir
;
Hsu, Shih-Ying
;
電子物理學系
;
Department of Electrophysics
We present the study of DC currents of an open dot generated from two time dependent electric fields in the absence of external bias Two electrical setups were applied. In one configuration. two fast oscillating voltages were applied on two side gates in the other one of the oscillating biases was directly applied to the source lead. The DC current as a function of frequency coupling strength and magnetic field was investigated The current is sinusoidally dependent with the phase shift and bilinearly dependent with the excitation voltage for both configurations However the current as a function of frequency coupling strength, and magnetic fields behaves differently in these two setups. The results indicate that the currents generated in different setups originate from different mechanisms and moreover not from any classical circuitry effect.
Time Dependent Electric Fields Generated DC Currents in a Large Gate-Defined Open Dot
(2010-11-01)
Liu, Kai-Ming
;
Umansky, Vladimir
;
Hsu, Shih-Ying
;
電子物理學系
;
Department of Electrophysics
We present the study of DC currents of an open dot generated from two time dependent electric fields in the absence of external bias Two electrical setups were applied. In one configuration. two fast oscillating voltages were applied on two side gates in the other one of the oscillating biases was directly applied to the source lead. The DC current as a function of frequency coupling strength and magnetic field was investigated The current is sinusoidally dependent with the phase shift and bilinearly dependent with the excitation voltage for both configurations However the current as a function of frequency coupling strength, and magnetic fields behaves differently in these two setups. The results indicate that the currents generated in different setups originate from different mechanisms and moreover not from any classical circuitry effect.