My PhD and postdoctoral research explores novel ordering states in quantum materials, with the aim to manipulate and control these states using "ultrafast" laser techniques. By tailoring the wavelength, polarization, and other properties of light pulses, specific electronic and crystal lattice degrees of freedom can be optically driven, without introducing electronic heating.
Because the macroscopic states of many quantum materials derive from a complex and delicate interplay between their charge, spin, and lattice ordering, even small--but targeted--perturbations can tip the balance between energetically similar competing orders. Or generate states that cannot be accessed by equilibrium methods, exposing new "dynamic" phase diagrams.
Tailored light excitation thus has the potential to inform future materials design, and offers a route to ultrafast materials control.
Projects & Techniques
Code & Tools
I completed my undergraduate education in physics at MIT in 2008 and entered the physics PhD program at UIUC the following fall. I joined Laura Greene's group in 2009 to study unconventional superconductivity at an exciting time, shortly after the discovery of iron-based superconductors.
From November 2010 through January 2015, I collaborated with Andrea Cavalleri's group at the MPI for the Structure and Dynamics of Matter in Hamburg, Germany. Here I've turned my attention to another class of superconductors, the high-Tc cuprates. My research focused on using ultrafast laser techniques to understand and manipulate phase competition in these materials, with the goal of promoting superconductivity. Most of my work involved probing light-induced states with time-domain THz spectroscopy.
I graduated with my PhD from UIUC in 2015 and the following fall I joined UC Berkeley as a Miller Research Fellow, working with Alessandra Lanzara. During my postdoc, I have developed new state-of-the-art capabilities that merge unprecedented high pulse energy, variable wavelength, narrowband light excitation capabilities with angle-resolved photoemission spectroscopy (ARPES), a workhorse in materials science for probing electronic behavior by mapping band structure. The optical design of the new system can also flexibly toggle to couple with a time-domain THz spectroscopy endstation, a complementary probe which can extract the complex optical response of materials.
"Dynamical decoherence of the light induced interlayer coupling in YBa2Cu3O6+δ,"
C. R. Hunt, D. Nicoletti, S. Kaiser, D. Proepper, M. Le Tacon, T. Loew, B. Keimer and A. Cavalleri.
"Two distinct kinetic regimes for the relaxation of light-induced superconductivity in La1.675Eu0.2Sr0.125CuO4,"
C. R. Hunt, D. Nicoletti, S. Kaiser, T. Takayama, H. Takagi, and A. Cavalleri.
"Femtosecond resonant soft x-ray diffraction links melting of charge order with light-enhanced coherent transport in YBa2Cu3O6.6,"
M. Först, A. Frano, S. Kaiser, R. Mankowsky, C. R. Hunt, J. J. Turner, G. L. Dakovski, M. P. Minitti, J. Robinson, T. Loew, M. Le Tacon, B. Keimer, J. P. Hill, A. Cavalleri, and S. S. Dhesi.
"Optically induced superconductivity in striped La2-xBaxCuO4 by polarization-selective excitation in the near infrared,"
D. Nicoletti, E. Casandruc, Y. Laplace, V. Khanna, C. R. Hunt, S. Kaiser, S. S. Dhesi, G. D. Gu, J. P. Hill, and A. Cavalleri.
"Optically induced coherent transport far above Tc in underdoped YBa2Cu3O6+δ,"
S. Kaiser, C. R. Hunt, D. Nicoletti, W. Hu, I. Gierz, H. Y. Liu, M. Le Tacon, T. Loew, D. Haug, B. Keimer, and A. Cavalleri.
Phys. Rev. B 89, 184516 (2014).
"Optically enhanced coherent transport in YBa2Cu3O6.5 by ultrafast redistribution of interlayer coupling,"
C. R. Hunt*, W. Hu*, S. Kaiser*, D. Nicoletti*, I. Gierz, M. C. Hoffmann, M. Le Tacon, T. Loew, B. Keimer and A. Cavalleri.
Nature Materials 13, 705–711 (2014).
"Detection of orbital fluctuations above the structural transition temperature in the iron pnictides and chalcogenides,"
H. Z. Arham, C. R. Hunt, W. K. Park, J. Gillett, S. D. Das, S. E. Sebastian, Z. J. Xu, J. S. Wen, Z. W. Lin, Q. Li, G. Gu, A. Thaler, S. Ran, S. L. Bud'ko, P. C. Canfield, D. Y. Chung, M. G. Kanatzidis, and L. H. Greene.
"Gap-like feature in the normal state of X(Fe1−x Cox)2As2, X = Ba, Sr and Fe1+yTe revealed by Point Contact Spectroscopy,"
H. Z. Arham, C. R. Hunt, W. K. Park, J. Gillett, S. D. Das, S. E. Sebastian, Z. J. Xu, J. S. Wen, Z. W. Lin, Q. Li, G. Gu, A. Thaler, S. L. Budko, P. C. Canfield, and L. H. Greene.
J. Phys.: Conf. Ser. 400, 022001 (2012).
"Design of new superconducting materials, and Point-Contact Spectroscopy as a probe of strong electron correlations,"
Laura H. Greene, Hamood Z. Arham, Cassandra R. Hunt, Wan Kyu Park.
J. of Supercond. and Novel Mag. 25, 2121-2126 (2012).
"Strong Coupling Superconductivity in Iron-Chalcogenide FeTe0.55Se0.45,"
W. K. Park, C. R. Hunt, H. Z. Arham, Z. J. Xu, J. S. Wen, Z. W. Lin, Q. Li, G. D. Gu, and L. H. Greene.