Current research projects

Nonlinear Photonic Topological Insulators (NoPhToI)

Funding agency: German Research Foundation

Budget: 200,000€

Summary: The aim of this project is to promote the understanding of new physical phenomena in disordered photonic topological materials, by using coupled optical waveguide systems. In particular, our theoretical and experimental research will address (1) Studies of topological nonlinear modes; (2) studies of novel lattice structures, in particular Lieb and Kagome geometries; (3) Studies of nonlinear wave dynamics in topological media with PT-symmetric lattice structure. Apart from revealing new and fundamental scientific knowledge, which is based on our sophisticated approach of using a highly controllable optical system (i.e., arrays of evanescently coupled waveguides), our results will have immediate technological significance, as they can be used in tele-communication and photonic data processing. We will take advantage of our superior fabrication technology that allows the individual addressing of numerous physical questions. We will combine the experimental work with theoretical analysis, in order to explain our results thoroughly and optimize device performance.


Alfried Krupp Research Prize

Funding agency: Alfried Krupp von Bohlen und Halbach Foundation

Budget: 1,000,000€

Summary: Since 1986, each year one prize is awarded to young professors at a German university in the field of natural and engineering sciences. This is one of the most prestigious German research prizes with particularly high endowment. The Alfried Krupp Research Prize shall allow the laureate to further improve his working environment and to push forward the scientific work in research and teaching.


Joint Invention, Visibility and Excellence (JIVE)

Funding agency: German Ministry of Science and Education

Budget: 80,000€

Summary: The mission of JIVE is to develop a R&D network based on a strong High-Tec platform for fabrication and functionalization of optical sensors, which provides efficient communication channels for the transfer of knowledge. This allows viable international connections along the value added chain, which by itself fosters and supports the transfer of technology between partners from industry and end users of sensor technology. Therefore, this project will have significant social impact such that people, their health as well as their environment will benefit in a sustainable manner. The main scientific and technological goal of JIVE is the development of novel technology approaches that can ultimately be transferred in enhanced optical sensors. To this end, the realization of photonic instruments with dimensions covering several orders of magnitude (100nm – 10cm) is of central importance. This will allow sensors that perfectly adapt to the conditions of applications with a particularly high demand on accuracy and manageability. Such applications are particularly important in the field of non-invasive diagnostics (e.g., cardiology, pneumotology, ophthalmology), for the detection of noxious substances in air and water, or for the characterization of biomedical substances in pharmacological industry.


Read more


Multi-scale laser system for the synchronized generation of high-power ultra-short laser pulses and high repetition pulse trains

Funding agency: German Research Foundation and the state of Mecklenburg-Vorpommern

Budget: 500,000€

Summary: The intense pulses supplied by this custom laser system allow for the highly localized deposition of energy within the bulk of transparent materials, a key requirement for the inscription of three-dimensional freeform photonic waveguide structures. As “circuitry for light”, intricate ensembles of such waveguides will drive several cutting-edge fields of research in the Solid-State Optics Group, including the complex nonlinear spatiotemporal dynamics of solitons and “light bullets”. Channeled by photonic lattices, light can be used to switch, route and modulate optical signals without the need for conventional slow electronics. Along a different avenue of research, the laser system will shed light on the formation of laser-induced refractive index changes by means of rapid pump-probe measurements with closely synchronized high- and low-energy pulses. The insights gained here will be instrumental the optimization of the waveguide inscription process and its adaptation to a wider range of functional materials for a new generation of advanced integrated optical circuits.


Error-Proof Bell-State Analyser (ErBeStA)

Funding agency: European Union

Budget: 270,000€

Summary: During this project, we will solve the long-standing problem of building a complete Bell-state analyser that is free from measurement errors. The realisation of such an error-proof Bell-state analyser constitutes a groundbreaking milestone for information technologies as it forms the key component for universal optical quantum computers and long-distance quantum communication. Reliable Bell-state detection will immediately impact the development of emerging quantum technologies, facilitate high-precision time-keeping and sensing, and enable future technologies such as secure communication or quantum cloud computing. This major conceptual and technological advancement will be made possible by combining two of the most recent breakthroughs at the frontier of quantum optics and nanophotonics: (i) ultra-strong quantum optical nonlinearities obtained from Rydberg-atom interactions or from a single quantum emitter strongly coupled to an optical microresonator and (ii) nanofabricated optical waveguide chips that permit high-level control of light propagation at the wavelength scale. Building the proposed Bell-state analyser will involve the development of advanced optical devices such as nondestructive photon-number-resolving detectors as well as configurable photon-number-specific filters and sorters, all of which constitute major scientific and technological breakthroughs on their own.


Addressing quantum eigenstates in integrated photonic structures

Funding agency: German Research Foundation

Budget: 200,000€

Summary: The aim of this project is to promote the understanding and control of waveguide architectures for coherent information transfer with the vision to establish a basis for new, quantum information processing applications. In particular, our research will address (1) Eigenstate formation and transmission in periodically driven lattice systems, (2) Tailored input state projection on system eigenstates, and (3) Transport studies of multi-photon states in lossy integrated optical networks. Therefore, the main goal of our proposal is to propose, implement and test a new approach for quantum information transfer. We will exploit the quantum eigenstates of the on-chip waveguide structures that in principle can travel indefinitely without any distortion due to their stationary nature. Apart from revealing new and fundamental scientific knowledge, which is based on our sophisticated approach of combining quantum state manipulation and optical integrated circuitry, our results will have immediate technological significance. We will combine the experimental work with theoretical analysis, in order to explain our results thoroughly and optimize device performance.


High precision positioning system for micro machining

Funding agency: European Union

Budget: 53,000€

Summary: The acquisition of a novel high precision positioning system has the ultimate goal of establishing new research directions within the field of optical micro machining using ultrashort laser pulses at the Institute of Physics. With the purchased apparatus, we are able to position a sample with nanometer precision with respect to an ultrashort pulse laser beam, which is vital for high precision modification of the sample material. A particular application of such high-precision material modifications is the fabrication of complex three-dimensional photonic waveguide structures in transparent bulk media. As “wires for light,” these devices constitute a fundamental component of integrated optical circuits. In combination with precisely tailored and positioned laser-induced micro- and nanostructures multiple degrees of freedom of photons are accessible for classical and quantum applications.


Optical transitions in photonic lattices

Funding agency: German Academic Exchange Service

Budget: 7,000€

Summary: This project focuses on the design and the fabrication of different linear photonic lattices with at least two flat bands in their dispersion relation. Our main aim is to explore the dependence of different optical transitions in the system on both the fabrication parameters and the parameters of system itself. During the seminal year of the project, we shall work on optical transitions in photonic lattices with alternating couplings whereas in the concluding project’s year we are going to examine light dynamics in lattices with more than one flat band in the bandgap diagram.


Photonic circuits for deterministic photon sources based on 2D materials

Funding agency: German Academic Exchange Service

Budget: 16,000€

Summary: This project will develop an approach to perform complete quantum tomography of a deterministic photon source on a chip. Our preliminary work indicates that this method will be stable, fast and scalable, allowing rapid characterization of the quality of photon sources and facilitating scaling to multi-photon states. Then we will extend this approach to the 2D-material-based deterministic generation of photon states entangled in time and space. The final step will be on-chip manipulation of complex entangled states and their applications to biological sensing and quantum communication


Emulation of the Graphene Structure using Photonics (E-GRAS)

Funding agency: German Research Foundation

Budget: 200,000€

Summary: In this project, we emulate the physics of graphene using optical waveguide arrays that are arranged in honeycomb geometry. Since the paraxial wave equation, which describes the propagation of light through the waveguide array, is mathematically equivalent to the Schrödinger equation, describing the time-evolution of electrons in graphene, the dynamics of a propagating light wave in a periodic refractive index modulation (a waveguide array) is similar to the evolution of an electronic wave function in the crystalline potential of a solid. This allows us to exploit the impact of strain and disorder on the graphene structure, to probing new states inaccessible to conventional graphene, and to control the existence of these states in the fabricated structures.


Light Propagation in Locally Symmetric Waveguide Arrays

Funding agency: German Research Foundation

Budget: 200,000€

Summary: In a close collaboration between theory and experiment in this project a new class of systems will be explored, which consist of units with different local symmetries. The aim of this research is the systematic study of optical-wave mechanical properties of locally symmetric materials with the ultimate goal of developing a deep understanding of wave evolution in those systems. This includes a new form of controlling light localization due to local symmetries, and the design and construction of perfectly transmitting resonances in fully locally symmetric waveguide structures.


Multipath Interference Tests in Quantum Mechanics

Funding agency: German Research Foundation

Budget: 200,000€

Summary: One of the key features of quantum mechanics is interference: if a particle can follow multiple paths towards a destination, all of these possibilities need to be taken into account to determine the chance of it ending up at the destination. However, this interference only considers all possible combinations of pairs of paths, but not three or more at a time. Our experiments using modern optical waveguide technology will test very precisely whether particles of light actually behave as quantum mechanics predicts, or whether there are deviations. At the same time we will explore theoretically how alternative theories could look like and how their predictions could be tested.


Photonic Topological Materials with Disorder (PhoToMaD)

Funding agency: German Research Foundation

Budget: 200,000€

Summary: The aim of this proposal is to promote the understanding of new physical phenomena in disordered photonic topological materials, by using coupled optical waveguide systems. In particular, our theoretical and experimental research will address (1) Studies of topologically protected edge transport in disordered media with broken timereversal symmetry (i.e., a topological Anderson insulator); (2) Studies of edge and bulk transport in disordered non-hermitian topological media; (3) Studies of nonlinear wave dynamics in disordered topological media (with either broken time-reversal symmetry or nonhermiticity).


Quantum Simulators – from Atomic to Photonic

Funding agency: German Research Foundation

Budget: 420,000€

Summary: A central theme of this project is the realization of ‘topological physics’ that would be difficult or impossible to implement otherwise. One example is the realization of the ‘Topological Anderson Insulator’ - a system that has quantized edge conductance when disorder is increased. We aim to explore this system and demonstrate the first “Topological Anderson Insulator”. Likewise, we plan to explore and demonstrate non-Hermitian parity-time (PT) symmetric topologically protected states – which are currently believed to be impossible. In yet another direction, we will investigate wave dynamics in systems emulating relativistic phenomena, going far beyond current experiments: light waves and ultracold atoms displaying highenergy effects such as Klein tunneling, and redshift/blueshift together with tidal forces at the vicinity of massive gravitational objects. In a many-body setting, proximity to a quantum critical point will allow us to observe relativistic ‘Higgs’ like modes in variable dimensions. The quantum simulators described in this proposal have the capacity to realize physics that would be impossible otherwise.


Radially Accelerating Light Waves (RALW)

Funding agency: German Research Foundation

Budget: 200,000€

Summary: It is the aim of this project to deepen the knowledge on so called Radially Self-Accelerating Beams (RABs). Our studies will cover theoretical as well as experimental aspects in order to cope with this very versatile field of research. In particular, we are going to answer the following questions: (1) How do the physical beam properties change under strong focusing conditions? (2) Is it possible to generate RABs efficiently? (3) Do numerical methods render beam tailoring possible in order to achieve specific spatial intensity distributions? (4) What are the advantages for laser material processing, especially in regards to laser drilling and photo lithography? (5) Is there a way to employ RABs for nano-particle manipulation and is it viable to control living cells as well?

Completed Projects

PICQUE

PICQUE

Title: Photonic Integrated Compound Quantum Encoding (PICQUE)

Funding agency: European Union

Budget: 250,000€

Summary: This Initial Training Network is at the core of European technological innovation. Excellence in science is guaranteed by the involvement of world-leading groups which founded this research area. All the basic components of a photonic quantum processor will be addressed: generation, manipulation and detection of photon states. Particular attention will be devoted to potential applications and on how to interface all the different components. We will establish a world-class training platform spreading around the highly interdisciplinar and intersectorial European-led area of quantum integrated photonics. By pushing the development of quantum optical technologies we foresee results of interest also for standard optical technologies. PICQUE will aims at forming the new generation of quantum information scientists, as well as figures being able to interact with the industry.

Nonlinear Circuits

Nonlinear Circuits

Title: Integrated Nonlinear Circuits for Broadband Quantum Optics

Funding agency: German Academic Exchange Service

Budget: 12,000€

Summary: This project will develop and demonstrate photonic devices for integrated generation, shaping, and routing of quantum states of light, based on ultrafast nonlinear optical interactions. Manipulation of photons entangled across a broad range of optical wavelengths will be achieved. This project will take advantage of complementary expertise of Australian and German partners in advanced fabrication technologies and their applications in photonic circuit development. The outcomes of the project will open new opportunities for the use of nonclassical photon states in the areas of information and communication, as well as imaging and sensing at extremely low-light few-photon levels for biological and security-related applications.

Enlightning New States of Matter

Enlightning New States of Matter

Titel: Enlightning New States of Matter

Funding agency: Thuringian Ministry for Economy, Science and Digital Society

Budget: 100,000€

Summary: In this project, the formation of a new state of matter based on crystalline phases in ferminonic condensates was investigated using lattices of evanescently coupled waveguides. Using a particular arrangement of the waveuides allows the emulation of the famous Gross-Neveu model, which in turn is the basis for the analysis of new fermonic states of matter.

Diamond Optics

Diamond Optics

Title: Diamond-/Carbon Based Optical Systems

Funding agency: German Ministry for Education and Research

Budget: 4,5000,000€

Summary: The work within the research project aims on the fundamental understanding of the propagation of optical waves in different systems, whose material parameter and structure are based on the different macroscopic manifestations of carbon. The main goal of the research is establishing organic and inorganic carbon-based and -inspired materials as optical materials in addition to the silicon-based optics dominating today, yielding eventually to various highly innovative applications in optical micro- and nanotechnology. 

Guided Light

Guided Light

Title:  Defect-free Confinement of Light Waves

Funding agency: German Research Foundation

Budget: 400,000€

Summary: This project within the German‐Canadian Research Training Group „Guided light – Tightly packed“ aims at understanding novel mechanisms for advanced light confinement will be studied, in theory and experiment, using classical and quantum light. The basis for all implementations will be arrays of evanescently coupled waveguides, which are one of the most prominent model systems for advanced physics concepts. In particular, they allow the extension of the investigated concepts from the Hermitian into the non-Hermitian domain, opening the gate to unravel further novel and unexpected phenomena.

Luminous Flow

Luminous Flow

Title:  Luminous Fluid Flow in 2d Structures: Experiment and Theory

Funding agency: German-Israeli Research Foundation

Budget: 200,000€

Summary: The goals of this research is the further development of analytical and numerical approaches for analysis of photonic flow equations, including proper consideration of quantum potentials and genuine quantum effects, applications of novel fabrication methods for complex waveguide structures, and experimental studies of a luminous liquid flow. This holds the promise of better insight into basic physical phenomena, from tunneling to "sonic" event horizons.

Quilmi

Quilmi

Title:  Quantum Integrated Light and Matter Interfaceory (QuILMI)

Funding agency: European Union

Budget: 100,000€

Summary: In this project, we developed a new technology for interfacing atoms with light that is based on holes intersecting on-chip laser-written waveguides. These holes, which form photonic cavities, are created by ultrashort laser pulses – a technique which is completely novel. We have demonstrated our ability to realise cavities of arbitrary shape and to drill holes through the entire photonic chip, which will be eventually used to store the atom molasses on the chip. Moreover, we demonstrated that these holes can also be used for connecting photonic fibres with the chip, to ensure a stable setup in the vacuum chamber.

Space Time

Space Time

Title: Correlated Photons in Integrated Optical Structures

Funding agency: Thuringian Ministry for Education, Science amd Culture

Budget: 110,000€

Summary: This project within the frame work of the collaborative research group „Space Time“ aims at understanding fundamental processes in the evolution of correlated photons in lattices of evanescently coupled waveguides. A focus of this project was the fabrication and characterization of systems with two transverse spatial dimensions that unravel new features based on dimensionality of quantum random walks.