Page 46 - Undergraduate Research Opportunities Program Proceedings 2017-18

School of Science
Department of Physics

with the methods in quantum statistical mechanics, the thermodynamic functions of fermi gas will be also deduced. Last
but not least, we will discuss the magnetization properties of the Fermi system.

Supervisor: WANG Ning / PHYS
Student: WAN Chun Yu / PHYS Course: UROP1000, Summer

This report covers the fundamental concepts behind the theory of magnetic oscillations, such as Landau levels, Fermi gas
and quantum statistical mechanics. The focus is on using the free electron model to derive two kinds of magnetic
susceptibility of metals. Pauli paramagnetism which originates from the spin magnetic moment of the electrons and
Landau diamagnetism which originates from the motion of electrons in a magnetic field. The degenerate limits and the
non-degenerate limits are derived with discussion on the accuracy and the neglected effects. Finally, the de Haas-van
Alphen effect in a two-dimensional system is briefly introduced as the degenerate limit of Landau diamagnetism which
exhibit oscillation in the magnetic susceptibility.

Charge Generation and Carrier Diffusion in Organic Solar Cells

Supervisor: WONG Kam Sing / PHYS
Student: CHEUNG Hon Ning / CHEM Course: UROP1000, Summer

Organic solar cells are one of the next generation photovoltaics due to its high mechanical flexibility, light weight and
low cost1. To meet the requirement before OPV being commercially available, challenges need to be overcome which
includes: unsatisfactory efficiency, short charge carrier lifetime and low stability due to unavoidable charge
recombination. In recent years, significant investigations have been conducted to overcome the technological and
material limitations while developing new organic photovoltaics devices with higher efficiency and commercial viability
collectively1-2. In this project, we focus on the study of charge recombination through. Transient photovoltage
measurements are conducted to evaluate the device performance through measuring the voltage decay lifetime (which
determines charge-carrier lifetime) and open-circuit voltage while varying background light intensity.

Supervisor: WONG Kam Sing / PHYS
Student: LI Veronica Qin Ting / PHYS Course: UROP1100, Fall
UROP2100, Spring
UROP3100, Summer

This report documents the first observations in this research project of strong photo-CELIV peaks in organic solar cells
(OSCs) fabricated at HKUST. Specifically, devices with thicker electron transport layers (ETLs) appeared likelier to display
photo-CELIV curves that are considerably greater in amplitude than the corresponding dark CELIV curves. However, such
devices were still RC time limited, as the decay time of transient photocurrent continues to change with shunt resistance.
More trials will need to be conducted on samples with active layers other than P3HT:PC61BM for a generalized
understanding of OSC properties during photo-CELIV measurements.

Dynamics of Housing Prices
Supervisor: WONG Michael Kwok Yee / PHYS
Student: FONG Kin Long / PHYS-IRE Course: UROP2100, Fall
UROP3100, Spring

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