Schedule Logo
Poster Session

Poster Session II

4:00 pm – 6:00 pm, Wednesday June 18 Session H00 Oregon Convention Center, Exhibit Hall E
Topics:
PrevNext

An Attosecond Entangled Photon Source for Attosecond Spectroscopy

Poster 34
Presenter: Tzu-Hsien Tan (Purdue University)
Authors: Eric Liu (Purdue University), Russell Zimmerman (Purdue University), Chris Greene (Purdue University), Niranjan Shivaram (Purdue University)

Attosecond pulses are crucial for measuring the electron dynamics of atoms and molecules on the attosecond time scale. Typical attosecond measurement use classical attosecond pulses to probe electron dynamics. Here we discuss progress towards generation of attosecond quantum light pulses in the form of entangled biphotons in the extreme-ultraviolet (XUV) regime. The entangled biphotons will be generated through two-photon decay of the 1s2s 1S0 metastable state in helium to the ground state. The total energy spacing is 20.62 eV, resulting in a photon pair correlation time on the order of attoseconds. A vacuum chamber and gas cell were designed and constructed, and a 240-nm laser is focused into the gas cell for a direct four-photon excitation of the metastable state. A single photon detection setup is being built to detect entangled photons from two-photon decay of metastable helium. The setup is composed of a photomultiplier tube and CaF2 windows. The photomultiplier tube detects the XUV photons, while the CaF2 windows select a band of photon energies between 8 – 10 eV.  A constant fraction discriminator and a time-to-digital converter are then employed to achieve higher signal-to-noise ratio. We discuss plans for applying the attosecond XUV entangled photons in attosecond pump-probe measurements.

Funding acknowledgement

We acknowledge support from the W.M. Keck Foundation.

POSTERS (156)