Angle-resolved photoemission spectroscopy with 9-eV photon-energy pulses generated in a gas-filled hollow-core photonic crystal fiber

TL;DR

This paper demonstrates a novel UV light source generated in a gas-filled hollow-core fiber for angle-resolved photoemission spectroscopy, enabling efficient, high-repetition-rate measurements of material band structures.

Contribution

It introduces a new gas-filled fiber-based UV source for ARPES, offering higher efficiency and potential for fast, high-resolution measurements.

Findings

Achieved VUV radiation between 5.5 and 9 eV using femtosecond pulses.

Measured the band structure of Bi2Se3 with high signal-to-noise ratio.

Promises time-resolved ARPES at hundreds of kHz or MHz repetition rates.

Abstract

A recently developed source of ultraviolet radiation, based on optical soliton propagation in a gas-filled hollow-core photonic crystal fiber, is applied here to angle-resolved photoemission spectroscopy (ARPES). Near-infrared femtosecond pulses of only few {\mu}J energy generate vacuum ultraviolet (VUV) radiation between 5.5 and 9 eV inside the gas-filled fiber. These pulses are used to measure the band structure of the topological insulator Bi2Se3 with a signal to noise ratio comparable to that obtained with high order harmonics from a gas jet. The two-order-of-magnitude gain in efficiency promises time-resolved ARPES measurements at repetition rates of hundreds of kHz or even MHz, with photon energies that cover the first Brillouin zone of most materials.