papers

Publications (45)

quant-ph2014

Temporal and spectral properties of quantum light

Birgit Stiller, Ulrich Seyfarth, Gerd Leuchs

The modes of the electromagnetic field are solutions of Maxwell's equations taking into account the material boundary conditions. The field modes of classical optics - properly nor…

physics.optics2025

Brillouin-enhanced four-wave mixing with optical chiral states

Xinglin Zeng, Birgit Stiller

Brillouin-enhanced four-wave mixing - also known as Brillouin dynamic gratings - is an important nonlinear effect in photonics that couples four light waves by travelling acoustic…

physics.optics2021

Stimulated Brillouin scattering in chiral photonic crystal fiber

Xinglin Zeng, Wenbin He, Micahel H. Frosz +5

Stimulated Brillouin scattering (SBS) has many applications, for example, in sensing, microwave photonics and signal processing. Here we report the first experimental study of SBS…

physics.optics2015

Depolarized guided acoustic wave Brillouin scattering in hollow-core photonic crystal fibers

Wenjia Elser née Zhong, Birgit Stiller, Dominique Elser +3

By performing quantum-noise-limited optical heterodyne detection, we observe polarization noise in light after propagation through a hollow-core photonic crystal fiber (PCF). We co…

quant-ph2014

Risk analysis of Trojan-horse attacks on practical quantum key distribution systems

Nitin Jain, Birgit Stiller, Imran Khan +3

An eavesdropper Eve may probe a quantum key distribution (QKD) system by sending a bright pulse from the quantum channel into the system and analyzing the back-reflected pulses. Su…

physics.optics2020

On-chip broadband non-reciprocal light storage

Moritz Merklein, Birgit Stiller, Khu Vu +3

Breaking the symmetry between forward and backward propagating optical modes is of fundamental scientific interest and enables crucial functionalities, such as isolators, circulato…

physics.optics2024

Brillouin-based storage of QPSK signals with fully tunable phase retrieval

Olivia Saffer, Jesús Humberto Marines Cabello, Steven Becker +2

Photonic memory is an important building block to delay, route and buffer optical information, for instance in optical interconnects or for recurrent optical signal processing. Pho…

physics.optics2017

Highly localized Brillouin scattering response in a photonic integrated circuit

Atiyeh Zarifi, Birgit Stiller, Moritz Merklein +6

The interaction of optical and acoustic waves via stimulated Brillouin scattering (SBS) has recently reached on-chip platforms, which has opened new fields of applications ranging…

quant-ph2022

Quantum coherent control in pulsed waveguide optomechanics

Junyin Zhang, Changlong Zhu, Christian Wolff +1

Coherent control of traveling acoustic excitations in a waveguide system is an interesting way to manipulate and transduce classical and quantum information. So far, these interact…

physics.optics2024

All-optical nonlinear activation function based on stimulated Brillouin scattering

Grigorii Slinkov, Steven Becker, Dirk Englund +1

Photonic neural networks have demonstrated their potential over the past decades, but have not yet reached the full extent of their capabilities. One reason for this lies in an ess…

physics.optics2022

Nonreciprocal vortex isolator by stimulated Brillouin scattering in chiral photonic crystal fibre

Xinglin Zeng, Philip St. J. Russell, Christian Wolff +3

Optical non-reciprocity, which breaks the symmetry between forward and backward propagating optical waves, has become vital in photonic systems and enables many key devices, such a…

physics.optics2023

An optoacoustic field-programmable perceptron for recurrent neural networks

Steven Becker, Dirk Englund, Birgit Stiller

A critical feature in signal processing is the ability to interpret correlations in time series signals, such as speech. Machine learning systems process this contextual informatio…

quant-ph2016

Attacks on practical quantum key distribution systems (and how to prevent them)

Nitin Jain, Birgit Stiller, Imran Khan +3

With the emergence of an information society, the idea of protecting sensitive data is steadily gaining importance. Conventional encryption methods may not be sufficient to guarant…

physics.optics2023

Spin-orbit interaction in nanofiber-based Brillouin scattering

Maxime Zerbib, Maxime Romanet, Thibaut Sylvestre +4

Angular momentum is an important physical property that plays a key role in light-matter interactions such as spin-orbit interaction. Here, we investigate theoretically and experim…

physics.optics2017

A chip-integrated coherent photonic-phononic memory

Moritz Merklein, Birgit Stiller, Khu Vu +2

Controlling and manipulating quanta of coherent acoustic vibrations - phonons - in integrated circuits has recently drawn a lot of attention, since phonons can function as unique l…

physics.optics2022

Optical vortex Brillouin laser

Xinglin Zeng, Philip St. J. Russell, Yang Chen +5

Optical vortices, which have been extensively studied over the last decades, offer an additional degree of freedom useful in many applications, such as optical tweezers and quantum…

quant-ph2016

Classically entangled optical beams for high-speed kinematic sensing

Stefan Berg-Johansen, Falk Töppel, Birgit Stiller +6

Tracking the kinematics of fast-moving objects is an important diagnostic tool for science and engineering. Existing optical methods include high-speed CCD/CMOS imaging, streak cam…

physics.optics2023

Brillouin light storage for 100 pulse widths

Birgit Stiller, Kevin Jaksch, Johannes Piotrowski +8

Signal processing based on stimulated Brillouin scattering (SBS) is limited by the narrow linewidth of the optoacoustic response, which confines many Brillouin applications to cont…

physics.optics2018

On-chip multi-stage optical delay based on cascaded Brillouin light storage

Birgit Stiller, Moritz Merklein, Christian Wolff +5

Storing and delaying optical signals plays a crucial role in data centers, phased array antennas, communication and future computing architectures. Here, we show a delay scheme bas…

physics.optics2025

Brillouin-Mandelstam Scattering-based Cooling of Traveling Acoustic Waves from Cryogenic Temperatures

Lisa Fischer, Laura Blázquez Martínez, Robin Chenivière +2

Thermal phonons are a major source of decoherence in quantum mechanical systems. Operating in the quantum ground state is therefore often an experimental prerequisite. Additionally…

quant-ph2016

Efficient single sideband microwave to optical conversion using an electro-optical whispering gallery mode resonator

Alfredo Rueda, Florian Sedlmeir, Michele C. Collodo +9

Linking classical microwave electrical circuits to the optical telecommunication band is at the core of modern communication. Future quantum information networks will require coher…

quant-ph2017

Quantum-limited measurements of optical signals from a geostationary satellite

Kevin Günthner, Imran Khan, Dominique Elser +13

The measurement of quantum signals that traveled through long distances is of fundamental and technological interest. We present quantum-limited coherent measurements of optical si…

physics.optics2019

Coherently refreshed acoustic phonons for extended light storage

Birgit Stiller, Moritz Merklein, Christian Wolff +4

Acoustic waves can serve as memory for optical information, however, acoustic phonons in the GHz regime decay on the nanosecond timescale. Usually this is dominated by intrinsic ac…

quant-ph2026

A solid-state quantum memory based on a continuous optoacoustic system

Changlong Zhu, Claudiu Genes, Birgit Stiller

Quantum memories for optical states are essential resources for quantum communication and information processing. We propose a quantum memory protocol based on coherent photon-phon…

physics.optics2026

Multi-dimensional parameter space of higher-order exceptional points induced by Brillouin optoacoustics

Grigorii Slinkov, Anton Montag, Julius T. Gohsrich +4

Exceptional points (EPs) are degeneracies in the spectrum of non-Hermitian systems, where both the eigenvalues and eigenvectors coalesce. In the vicinity of an n-th order EP, the e…

physics.optics2024

Frequency conversion of vortex states by chiral forward Brillouin scattering in twisted photonic crystal fibre

Xinglin Zeng, Philip St. J. Russell, Birgit Stiller

Optical vortex states-higher optical modes with helical phase progression and carrying orbital angular momentum-have been explored to increase the flexibility and capacity of optic…

physics.optics2025

Cavity-less Brillouin strong coupling in a solid-state continuous system

Laura Blázquez Martínez, Changlong Zhu, Birgit Stiller

Strongly coupling two systems allows them to exchange coherent information before the systems decohere. This important regime in light-matter interactions has predominantly been re…

physics.app-ph2018

On-chip correlation-based Brillouin sensing: design, experiment and simulation

Atiyeh Zarifi, Birgit Stiller, Moritz Merklein +10

Wavelength-scale SBS waveguides are enabling novel on-chip functionalities. The micro- and nano-scale SBS structures and the complexity of the SBS waveguides require a characteriza…

physics.optics2018

Crosstalk-free multi-wavelength coherent light storage via Brillouin interaction

Birgit Stiller, Moritz Merklein, Khu Vu +4

Stimulated Brillouin scattering drives a coherent interaction between optical signals and acoustic phonons and this effect can be used for storing optical information in acoustic w…

physics.optics2016

Cascaded forward Brillouin scattering to all Stokes orders

Christian Wolff, Birgit Stiller, Benjamin. J. Eggleton +2

Inelastic scattering processes such as Brillouin scattering can often function in cascaded regimes and this is likely to occur in certain integrated opto-acoustic devices. We devel…

quant-ph2023

Optoacoustic cooling of traveling hypersound waves

Laura Blázquez Martínez, Philipp Wiedemann, Changlong Zhu +2

We experimentally demonstrate optoacoustic cooling via stimulated Brillouin-Mandelstam scattering in a 50 cm-long tapered photonic crystal fiber. For a 7.38 GHz acoustic mode, a co…

cs.ET2025

Roadmap on Neuromorphic Photonics

Daniel Brunner, Bhavin J. Shastri, Mohammed A. Al Qadasi +147

This roadmap consolidates recent advances while exploring emerging applications, reflecting the remarkable diversity of hardware platforms, neuromorphic concepts, and implementatio…

physics.optics2026

Magnon-mediated microwave to optical time dynamics

Rajkumar Jadhav, Xinglin Zeng, Cedric Traub +6

Optomagnonic modulation techniques are an emerging platform for information transfer from the microwave to the optical domain. However, these techniques focus largely on the spectr…

quant-ph2024

Optoacoustic entanglement in a continuous Brillouin-active solid state system

Changlong Zhu, Claudiu Genes, Birgit Stiller

Entanglement in hybrid quantum systems comprised of fundamentally different degrees of freedom, such as light and mechanics is of interest for a wide range of applications in quant…

quant-ph2020

Agile and versatile quantum communication: signatures and secrets

Stefan Richter, Matthew Thornton, Imran Khan +7

Agile cryptography allows for a resource-efficient swap of a cryptographic core in case the security of an underlying classical cryptographic algorithm becomes compromised. Convers…

physics.optics2023

High-speed coherent photonic random-access memory in long-lasting sound waves

Andreas Geilen, Steven Becker, Birgit Stiller

In recent years, remarkable advances in photonic computing have highlighted the need for photonic memory, particularly high-speed and coherent random-access memory. Addressing the…

quant-ph2022

Dynamic Brillouin cooling for continuous optomechanical systems

Changlong Zhu, Birgit Stiller

In general, ground state cooling using optomechanical interaction is realized in the regime where optical dissipation is higher than mechanical dissipation. Here, we demonstrate th…

physics.optics2026

Giant Brillouin gain in frozen CS2 capillaries

Simon Seiderer, Andreas Geilen, Luan N. Sliwa +5

Stimulated Brillouin-Mandelstam scattering offers exceptional capabilities for photonic signal processing, but current platforms demand performance trade-offs between long interact…

quant-ph2023

Eavesdropper localization for quantum and classical channels via nonlinear scattering

Alexandra Popp, Florian Sedlmeir, Birgit Stiller +1

Optical fiber networks are part of important critical infrastructure and known to be prone to eavesdropping attacks. Hence cryptographic methods have to be used to protect communic…

physics.optics2026

Higher-order exceptional points in a multimode continuum optoacoustic system

Anton Montag, Julius T. Gohsrich, Quentin Levoy +2

Exceptional points appear in non-Hermitian systems as degeneracies, where not only eigenvalues but also eigenvectors coalesce. They are of great theoretical and experimental intere…

physics.optics2026

Two-spin-multiplexed optoacoustic light storage in chiral photonic crystal fiber

Xinglin Zeng, Linqiao Gan, Jesús Humberto Marines Cabello +2

The ability to coherently store and manipulate optical information across multiple degrees of freedom is a central requirement for scalable quantum information processing and multi…

physics.optics2018

Brillouin spectroscopy of a hybrid silicon-chalcogenide waveguide with geometrical variations

Atiyeh Zarifi, Birgit Stiller, Moritz Merklein +10

Recent advances in design and fabrication of photonic-phononic waveguides have enabled stimulated Brillouin scattering (SBS) in silicon-based platforms, such as under-etched silico…

quant-ph2015

Satellite Quantum Communication via the Alphasat Laser Communication Terminal

Dominique Elser, Kevin Günthner, Imran Khan +12

By harnessing quantum effects, we nowadays can use encryption that is in principle proven to withstand any conceivable attack. These fascinating quantum features have been implemen…

physics.optics2022

Exploring extreme thermodynamics in nanoliter volumes through stimulated Brillouin-Mandelstam scattering

Andreas Geilen, Alexandra Popp, Debayan Das +6

Examining the physical properties of materials - particularly of toxic liquids - under a wide range of thermodynamic states is a challenging problem due to the extreme conditions t…

physics.optics2021

Picosecond acoustic dynamics in stimulated Brillouin scattering

Johannes Piotrowski, Mikołaj K. Schmidt, Birgit Stiller +2

Recent experiments demonstrating storage of optical pulses in acoustic phonons based on stimulated Brillouin scattering raise a number of questions about the spectral and temporal…