Walter Scott, Jr. College of Engineering

Graduate Exam Abstract

Liang Yin
Ph.D. Preliminary
Dec 11, 2015, 12:15 pm - 3:15 pm
A210 ERC
Comprehensive characterization of laser-created Gd and Tb plasma emission near λ = 6.7nm
Abstract: We have conducted a comprehensive
characterization of Gd and Tb laser-
created plasmas radiating beyond
extreme ultraviolet (BEUV) emission at
wavelengths from 6.5 to 6.7 nm over a
broad range of laser irradiation
parameters using a single laser with
tunable pulse duration. Measurements
were conducted by focusing λ = 1030
nm laser pulses with durations ranging
from 120 ps to 4ns onto planar
targets. The angular distribution of
the in-band BEUV emission yield was
measured using an array of calibrated
energy-monitors to obtain an accurate
measurement of conversion efficiency.
The peak of the BEUV emission
spectra was observed to shift with
pulse duration of the driver laser
pulses resulting with the Gd plasma
emission driven by nanosecond laser
pulses best matching the reflectivity
bandwidth of available La/B4C
multilayer mirrors near λ = 6.7 nm.
The variation of the spectral
distribution was also measured as a
function of laser pulse duration and
angle respectively to better
understand the plasma conditions. In
order to study fine spectral structure
of Gd plasma a spatially resolved
spectral profile of Gd plasma was
obtained. Images of the plasma as a
function of three major driver laser
parameters including intensity, pulse
duration, and focal spot size were also
obtained. A maximum conversion
efficiency of 0.47% for Gd plasma and
0.45% for Tb plasma respectively
within a 0.6% bandwidth was obtained.
The measured spectra and the
plasma images were used to elucidate
the plasma physics behind the
observed trends.
Adviser: Jorge J. Rocca
Co-Adviser: NA
Non-ECE Member: Azer P. Yalin, Mechanical Engineering
Member 3: Mario C. Marconi, Electrical and Computer Engineering
Addional Members: Carmen S. Menoni, Electrical and Computer Engineering
Efficient excitation of gain-saturated sub-9-nm-wavelength tabletop soft-X-ray lasers and lasing down to 7.36 nm
D Alessi, Y Wang, BM Luther, L Yin, DH Martz, MR Woolston, Y Liu, ...
Physical Review X 1 (2), 021023

Relativistic plasma nanophotonics for ultrahigh energy density physics
MA Purvis, VN Shlyaptsev, R Hollinger, C Bargsten, A Pukhov, A Prieto, ...
Nature Photonics 7 (10), 796-800

Wavefront improvement in an injection-seeded soft x-ray laser based on a solid-target plasma amplifier
L Li, Y Wang, S Wang, E Oliva, L Yin, TT Thuy Le, S Daboussi, D Ros, ...
Optics letters 38 (20), 4011-4014

Gain dynamics in a soft-X-ray laser amplifier perturbed by a strong injected X-ray field
Y Wang, S Wang, E Oliva, L Li, M Berrill, L Yin, J Nejdl, BM Luther, ...
Nature Photonics 8 (5), 381-384

Single-shot soft x-ray laser linewidth measurement using a grating interferometer
Y Wang, L Yin, S Wang, MC Marconi, J Dunn, E Gullikson, JJ Rocca
Optics letters 38 (23), 5004-5007
Program of Study:
ECE 506
ECE 604
ECE 641
ECE 650
ECE 799
MATH 531