Internships

We are seeking interns at the Lawrence Berkeley National Laboratory. 

Please send email to Antoine İşlegen-Wojdyla (awojdyla@lbl.gov) with cv/resume.
Other topics related to coherent x-ray optics or machine learning for optics may be discussed.

The interns  will work on one of the following topics:

Fourier-Transform X-Ray Interferometer

We are collaborating with JPL to build a soft x-ray Fourier Transform interferometer, where the incident beam is split by a polka dot membrane made of a low-stress nitride membrane (with <2nm-rms surface error.) We want to align the interferometer, develop data acquisition and data processing using visible light, and demonstrate Fourier-Transform spectroscopy on a synchrotron beamline at a 65 eV photon energy. More info: https://doi.org/10.1117/12.859147

Adaptive optics for nano-FTIR

The Advanced Light Source beamline is operating a nano Fourier Transform Infrared imager, where a broadband infrared beam from the synchrotron is coupled to an Atomic Force Microscope tip to provide IR spectroscopy capabilities with nanometer spatial resolution. We have acquired an adaptive optics system (a wavefront sensor and a deformable mirror) to correct the aberration caused by the heating of the entrance mirror (subject to kW of power over a few square millimeters.) We need to build the optical setup and the instrument controls to perform wavefront correction.

Efficient simulation of orbital angular momentum in soft x-ray beam caused by Artificial Spin Ice. 

We want to model the interaction of a soft x-ray beam (photon energy 700 eV corresponding to 1.8 nm wavelength) with an artificial spin ice structure capable of generating orbital angular momentum in the beam. These simulations will involve custom optics propagation method (e.g. Huygens-Fresnel formulation rather than Fourier optics) to match the length scale of the experiments

https://als.lbl.gov/spiraling-beams-differentiate-antiferromagnetic-states/

Spatial and angular coherence filtering of higher harmonics in an insertion device on a diffraction-limited storage ring with finite energy spread

 The Advanced Light Source will undergo an upgrade of its storage ring to provide a mostly coherent soft x-ray photon beam (>50% coherence at 1keV.) However, when operating at higher photon energy, there is a degradation of the coherence of the beam due to the finite energy spread of the storage ring. We want to simulate these effects that become dominant on higher harmonics of an insertion device, and find ways to mitigate their effect on the partial coherence of the beam. The simulations will be done using the Synchrotron Radiation Workshop (SRW), a wavefront propagation code, and performed on the NERSC super computer hosted at Berkeley Lab