Walter Scott, Jr. College of Engineering

Graduate Exam Abstract

David Alessi
Ph.D. Final
Sep 23, 2011, 1:15 pm
Wagar 231
Abstract: This dissertation describes the development of table-top soft X-ray lasers with wavelengths ranging from 30 nm to 7.4 nm. The laser transisitons occur within collisionally excited states of nickel-like and neon-like ions which are created from laser ablation of solid targets. An Nd:glass slab laser system was developed to provide 20J (and then upgraded to 40J) of laser light at 527 nm for pumping a table-top chirped pulse amplification Ti:sapphire laser. With this increase in pump energy, the Ti:sapphire system is capable of producing 12J uncompressed laser pulses at a 1Hz repetition rate. Stretched and compressed pulses from this Ti:sapphire laser system operating near 800 nm are used to both ionize the material to a high degree and heat the free electrons in these plasmas to temperatures required for high gain. Simulations from a 1.5D hydrodynamic/atomic model indicate a peak gain of 90 cm-1 for the 8.8 nm laser transition in nickel-like lanthanum is reached with an electron temperature of ~850 eV, and a density of 6×1020 cm-3. By using the grazing incidence pumping geometry gain saturated operation was demonstrated in the 2p53p1S0?2p53s1P1 transition of neon-like titanium (? = 32.6 nm) and vanadium (? = 30.4 nm) as well as in the 3d94d1S0?3d94p1P1 transition in nickel-like tellurium (? = 10.9 nm), and lanthanum (? = 8.8 nm). Strong lasing was also demonstrated in the same neon-like transition in chromium (? = 28.6 nm), as well as the same nickel-like transition in cerium (? = 8.5 nm), praseodymium (? = 8.2 nm), neodymium (? = 7.9 nm) and samarium (? = 7.4 nm). This is this first demonstration the generation of bright gain-saturated sub-9-nm wavelengths with a table-top laser operating at 1-Hz repetition rate. The short wavelength, microjoule pulse energy, picosecond pulse duration, and repetitive operation of these lasers will enable new applications such as sequential imaging of ultrafast nano-scale dynamic phenomena to be realized on a table top.
Adviser: Jorge Rocca
Co-Adviser: N/A
Non-ECE Member: Siu Au Lee, Physics
Member 3: Carmen Menoni, ECE
Addional Members: Mario Marconi, ECE
L. M. Meng, D. Alessi, O. Guilbaud, Y. Wang, M. Berrill, B. M. Luther, S. R. Domingue, D. H. Martz, D. Joyeux, S. De Rossi, J.J. Rocca, and A. Klisnick, "Temporal coherence and spectral linewidth of an injection-seeded transient collisional soft x-ray laser," Optics Express 19, 12087 (2011)
D. Alessi, D. H. Martz, Y. Wang, M. Berrill, B. M. Luther and J. J. Rocca, “Gain-saturated 10.9 nm tabletop laser operating at 1 Hz repetition rate,” Optics Letters 35, 414 (2010)
M. Berrill, D. Alessi, Y. Wang, S. R. Domingue, D. H. Martz, B. M. Luther, Y. Liu and J. J. Rocca, “Improved beam characteristics of solid-target soft x-ray laser amplifiers by injection-seeding with high harmonics,” Optics Letters 35, 2317 (2010)
D. H. Martz, D. Alessi, B. M. Luther, Y. Wang, D. Kemp, M. Berrill and J. J. Rocca, ”High Energy 13.9 nm Table-top Soft X-ray Laser at 2.5 Hz Repetition Rate Excited by a Slab-pumped Ti:sapphire Laser,” Optics Letters 35, 1632 (2010)
F. Brizuela, S. Carbajo, A. Sakdinawat, D. Alessi, D. Martz, Y. Wang, B. Luther, K. A. Goldberg, I. Mochi, D. T. Attwood, B. La Fontaine, J. J. Rocca, and C. S. Menoni, “Extreme Ultraviolet Laser-based Table-Top Aerial Image Metrology of Lithographic Masks,” Optics Express 18, 14467 (2010)
D. H. Martz, H. T. Nguyen, D. Patel, J. A. Britten, D. Alessi, E. Krous, Y. Wang, M. A. Larotonda, J. George, B. Knollenberg, B. M. Luther, J. J. Rocca and C. S. Menoni, “Large area high efficiency broad bandwidth 800 nm dielectric gratings for high energy laser pulse compression.” Optics Express 17, 23809-23816 (2009)
Y. Wang, E. Granados, F. Pedaci, D. Alessi, B. Luther, M. Berrill, and J.J. Rocca, “Phase-coherent, injection-seeded, table-top soft-x-ray lasers at 18.9 nm and 13.9 nm,” Nature Photonics 2, 94 (2008)
A. Weith, M.A. Larotonda, Y. Wang, B.M. Luther, D. Alessi, M.C. Marconi, J.J. Rocca, and J. Dunn, “Continuous high repetition rate operation of collisional soft x-ray lasers using solid targets,” Optics Letters 31, 1994 (2006)
B.M. Luther, Y. Wang, M.A. Larotonda, D. Alessi, M. Berrill, J.J. Rocca, J. Dunn, R. Keenan, and V.N. Shlyaptsev, “High Repetition Rate Collisional Soft X-Ray Lasers Based on Grazing Incidence Pumping,” IEEE Journal of Quantum Electronics 42, 4 (2006)
Y. Wang, M.A. Larotonda, B.M. Luther, D. Alessi, M. Berrill, V.N. Shlyaptsev, and J.J. Rocca, “Demonstration of high-repetition-rate tabletop soft-x-ray lasers with saturated output at wavelengths down to 13.9 nm and gain down to 10.9 nm,” Physical Review A 72, 053807 (2005)
J.J. Rocca, Y. Wang, M.A. Larotonda, B.M. Luther, M. Berrill, and D. Alessi, “Saturated 13.2 nm high-repetition-rate laser in nickellike cadmium,” Optics Letters 30, 2581 (2005)
B.M. Luther, Y. Wang, M. Berrill, D. Alessi, M.C. Marconi, M.A. Larotonda, and J.J. Rocca, “Highly Ionized Ar Plasma Waveguides Generated by a Fast Capillary Discharge,” IEEE Transactions on Plasma Science 33, 582 (2005)
D. Alessi, B.M. Luther, Y. Wang, M.A. Larotonda, M. Berrill, and J.J. Rocca, “High repetition rate operation of saturated table-top soft x-ray lasers in transitions of neon-like ions near 30 nm,” Optics Express 13, 2093 (2005)
B.M. Luther, Y. Wang, M.A. Larotonda, D. Alessi, M. Berrill, M.C. Marconi, J.J. Rocca, and V.N. Shlyaptsev, “Saturated high-repetition-rate 18.9-nm tabletop laser in nickellike molybdenum,” Optics Letters 30, 165 (2005)
M.A. Larotonda, B.M. Luther, Y. Wang, Y. Liu, D. Alessi, M. Berrill, A. Dummer, F. Brizuela, C.S. Menoni, M.C. Marconi, V.N. Shlyaptsev, J. Dunn, and J.J. Rocca, “Characteristics of a Saturated 18.9-nm Tabletop Laser Operating at 5-Hz Repetition Rate,” IEEE Journal of selected topics in Quantum Electronics 10, 1363 (2004)
Program of Study: