Research

In this project we study the quantum optical interactions of relativisitic (70% of the speed of light) free electrons with quantum emitters such as perovskite quantum dots and nitrogen vacancy centers in diamond. Although the electrons are relativisitic, our system allows us to easily observe even a single photon exchange in their energy gain and loss spectrum. With this strong tool, we are looking for collective superradiant interactions between the free electrons and the quantum emitters.

In this project we study the nonlinear interactions between pulses of light in a fiber laser. Solitons are special types of localized waves which mantain their shape while propagating. Being nonlinear creatures, solitons can interact, collide and form bound states. We found that we can induce a transition between incoherent and coherent bound states of solitons by scanning the laser gain, controling their separation over two orders of magnitude and transitioning between a relative phase-fluctuating and a phase-locked state. We also modeled this transition theoretically utilizing the recently devoloped noise mediated interaction foralism for ultra-long range soliton interactions.
Relavent publications:
[1] Kfir Sulimany*, Offek Tziperman*, Yaron Bromberg, and Omri Gat. "Soliton-pair dynamical transition in mode-locked lasers." Optica 9, no. 11 (2022): 1260-1267.

In 1954 Robert Dicke refined our understanding of spontaneous emission by showing that identical emitters, coupled identically to an electromagnetic field will exhibit either enhanced or suppressed emission due to constructive or destructive interference between decay paths, superradiance and subradiance. In this project we studied the quantum optical state of light emitted from a system of quantum entangled emitters, we studied the affects of emitters positions, interactions, losses, initial conditions and more, showing how these degrees of freedom can be leveraged for creating quantum states of light that are important for quantum technologies.
Relavent publications:
[1] Offek Tziperman†, Gefen Baranes†, Alexey Gorlach†, Ron Ruimy, Michael Faran, Nir Gutman, Andrea Pizzi, and Ido Kaminer. ”Spontaneous emission from correlated emitters.” Under review,arXiv:2306.11348 (2023).
[2] Nir Gutman†, Alexey Gorlach†, Offek Tziperman, Ron Ruimy, and Ido Kaminer. ”Universal control of symmetric states using spin squeezing.” Accepted to Physical Review Letters, arXiv:2312.01506 (2023).

It has long been known that there is a deep connection between nonlinear physics and quantum optics, and that creation and manipulation of quantum states of light requires nonlinearity. Most of the interesting phenomena in nonlinear optics are tightly connected to the inherently multimode nature of light, such as the generation of new frequencies via nonlinear processes. Nevertheless, the multimode aspects of nonlinearities in quantum optics have received only little attention. We study the multimode transformations of pulses through Hamiltonians that are quadratic in creation and anhilation operators, describing many fundamental operations: from beam splitters and interferometers, dispersion, diffraction and polarization rotation, to nonlinear affects such as parametric amplification, parametric down conversion and frequency conversion. One finding of special importance is that parametric amplification of quantum pulses is vastly different than its single mode counterpart and that a multimode model is crucial for describing current leading experiments in the field. We also find a suprising result: An input quantum pulse will transfer information on its quantum state content to a maximum of two temporal modes on the output!
Relavent publications:
[1] Offek Tziperman†, Victor Rueskov Christiansen†, Ido Kaminer, and Klaus Mølmer. ”Parametric amplification of a quantum pulse.” Submitted to Physical Review Letters, arXiv:2312.04394 (2023).

Many galaxies at high redshift are clumpy, meaning they have areas that are overdense compared to the sorroundings. Clumps are formed when the force of gravitation overcomes the forces due to pressure and rotation causing a local inward collapse of mass. Studying massive clumps in high redshift, we look into the survivability of clumps. Some clumps are relatively short lived, disrupting over a few Myr while others are long lived living for hundreds of Myr. The goal of the project is to understand what determines the fate of a clump, whether it will be short lived (SLC) or long lived (LLC). We use a combination of analytical modeling and data analysis of pre-existing heavy numerical simulations. We take into account the feedback from supernova. Here is an example of a simulated clump evolving in time and converting its gas into stars.
Relavent publications:
[1] Avishai Dekel, Offek Tziperman, Kartick C. Sarkar, Omri Ginzburg, Nir Mandelker, Daniel Ceverino, and Joel Primack. ”Conditions for clump survival in high-z disc galaxies.” Monthly Notices of the Royal Astronomical Society 521, no. 3 (2023): 4299-4322.

Scintillation, the emission of light by materials when absorbing high-energy quanta or particles, has applications in medical imaging and particle physics experiments. Accurate measurements of scintillator properties—yield, energy resolution, and lifetime—are essential both during the development and the use of scintillators. In this project, we study how the quantum optical properties of scintillation light can help us characterize scintillators and even improve their signal to noise ratio.
Relavent publications:
[1] Shaul Katznelson, Offek Tziperman, Tomer Bucher, Tom Lenkiewicz Abudi, Roman Schuetz, Orr Be’er, Shai Levy, Yehonadav Bekenstein, Charles Roques-Carmes, and Ido Kaminer ”X-ray Driven Photon Bunching.” CLEO 2023, paper SM1H.6., full paper in preparation.