Antoinette J. Taylor

Efficient high-energy pulse-train generation using a 2 n -pulse Michelson interferometer

We demonstrate a novel, Michelson-based, ultrafast multiplexer with a throughput approaching 100% for a polarization-multiplexed train and 50% for a linearly polarized train, which is compatible with a high-energy pulse train and shaped-pulse generation. The interpulse spacings in the resultant 2(n)-pulse train can be adjusted continuously from multinanoseconds through zero. Using this interferometer, we also demonstrate generation of a 16-pulse train of terahertz pulses.

Probing Intraband Conductivity Dynamics in Graphene

We use ultrafast optical spectroscopy to investigate intraband conductivity dynamics in a graphene monolayer grown by chemical vapor deposition, revealing the effect of the conical band structure on two-dimensional Dirac quasiparticles.

Using Ultrafast Optical Spectroscopy to Unravel the Properties of Correlated Electron Materials

Ultrafast optical spectroscopy has attained prominence over the last few decades due to its ability to resolve dynamics in conventional metals and semiconductors at the fundamental time scales of electron and lattice motion. More recently, this technique has been used to study correlated electron materials, shedding new light into not only their dynamic behavior, but also their intrinsic properties. Here, we will describe the ability of ultrafast optical spectroscopic techniques to provide deep insight into different classes of correlated electron materials that often cannot be attained using any other technique.

Materials Frontiers to Empower Quantum Computing

This is an exciting time at the nexus of quantum computing and materials research. The materials frontiers described in this report represent a significant advance in electronic materials and our understanding of the interactions between the local material and a manufactured quantum state. Simultaneously, directed efforts to solve materials issues related to quantum computing provide an opportunity to control and probe the fundamental arrangement of matter that will impact all electronic materials. An opportunity exists to extend our understanding of materials functionality from electronic-grade to quantum-grade by achieving a predictive understanding of noise and decoherence in qubits and their origins in materials defects and environmental coupling. Realizing this vision systematically and predictively will be transformative for quantum computing and will represent a qualitative step forward in materials prediction and control.

Ultrafast Observation of the Coexistence of Antiferromagnetism and Superconductivity in a High-T c Superconductor

Ultrafast quasiparticle dynamics of the high-Tcsuperconductor Tl2Ba2Ca2Cu3Oywere probed using the all-optical pump-probe technique. Our results are consistent with the coexistence of antiferromagnetism and superconductivity at low temperatures.

Ultrafast Carrier Dynamics in Semiconductor Nanowires

Time-resolved measurements of carrier dynamics in Ge and GaN nanowires reveal that carrier relaxation in these systems is governed by surface states and defects. This has significant implications for nanowire-based devices in photonics and thermoelectrics.

Ultrafast Dynamics of the Itinerant Antiferromagnet UNiGa 5

Time-resolved photoinduced reflectivity data for the itinerant antiferromagnet UNiGa5 showed a divergence of the relaxation time near TN due to the opening of a spin gap, and at the lowest temperatures indicative of spin-fluctuation scattering.

Terahertz Surface Plasmon Polariton Coupling via Gratings and Prisms

Terahertz time-domain spectroscopy is used to study coupling to surface plasmon polaritons via silicon prisms and metallic gratings. Grating measurements indicate efficient, narrowband coupling, while prism measurements show broadband coupling and propagation over ~6.3cm.

Terahertz Emission Spectroscopy of Ultrafast Demagnetization in Iron

We have observed ultrafast demagnetization of ferromagnetic metals after femtosecond pump pulse excitation by both transmission and emission spectroscopy. We observe demangtization occuring in iron with a 2 ps time constant.

Multi-pulse Interferometric FROG

By now you’re well aware that in just ten years the measurement of ultrashort light pulses has advanced from practically impossible to nearly indispensable. FROG and related techniques see daily use in labs around the world. Moreover, FROG’s self-consistency checks have firmly established it as the gold standard of pulse measurement. In addition, a rarely touted feature of FROG is that it is a type of ultrafast BOXCAR integrator, gating only the pulse and not undesired cw backgrounds. Indeed, if your goal is to characterize a pulse, FROG is undoubtedly the right choice.