11 innovations from Bar-Ilan University, available for licensing, co-investment, or spin-out through BIRAD.
Adi Makmal
Variational quantum algorithms (VQAs) is a recent family of quantum algorithms, applicable for a large set of theoretical and industrial optimization problems, form computational chemistry, through combinaotrial problems to machine learning tasks. All these problems are classically intractable and the hope is that quantum computers through VQAs could offer better or more efficient solutions. However, despite significant research efforts, their performance often falls short. Pulse optimization strategies for VQAs operate directly at the pulse level instead of following the traditional gate optimization process. This approach provides more adaptability and the potential for quicker execution. In the invention presented here, we further develop a freestyle pulse optimization method which doesn't set specific limitations on the pulse form beyond those that are set by the hardware itself. Rather, the pulse is broken down into a sequence of constant-amplitude pulses, with each one being fine-tuned individually. In comparison to previous literature, our scheme stands out in that in addition to each qubit having its own distinct freestyle pulse channel, which is optimized individually, we also account for a dedicated channel for every qubit pair, as natively designed in several super conducting qubit platforms, thereby ensuring optimal flexibility and expressiveness.
Peer Avraham
The discovery describes an innovative source of broad-band, highly-coherent quantum light and high-efficiency photon-pair generation with low pump power. Additionally, a novel method for self-measurement of the quantum coherence is described - the source itself can be used to measure its own performance. The source is based on a nonlinear crystal with polished and coated end facets to create a monolithic broad-band Optical Parametric Oscillator (OPO). Its advantages over common sources of nonlinear crystals in single-pass include: 1. A monolithic OPO provides ideal coherence quality due to minimizing internal losses to a minimum. 2. The required pump power for a given photon flux is low. The threshold for lasing in such a source can be low (less than 5 watts, sometimes down to hundreds of milliwatts, depending on design). 3. Integral dispersion compensation in the crystal mirrors ensures a maximal bandwidth of tens of nanometers and above, generating many pairs of squeezed photons and allowing for a very high flux of entangled photons - up to terahertz pairs per second, which is a significant advantage for quantum communication applications in wavelength-division multiplexing. 4. Mode spacing convenient for telecom (around 10 GHz) in the telecommunication range (1550 nanometers) allows for the construction of separate channels, which is crucial for communication applications. 5. The monolithic design of the OPO ensures passive stability, which facilitates the feedback loop for stabilizing the pump laser to the resonator frequency. Moreover, the concentric design of the resonator ensures stability and resistance to spatial misalignments. Furthermore, the discovery includes a method for self-measurement of the generated coherence using parametric homodyne detection within the crystal itself. Specifically, by operating the monolithic source in a ring resonator configuration, the source can be used in one direction (with the clock) to generate quantum light, and in the opposite direction for measurement, enabling wide-bandwidth homodyne-based measurement, as described in the accompanying documents. Together, the source and measurement method provide a foundation for various applications of quantum technology, such as secure quantum communication (QKD) and wide-bandwidth quantum sensing.
Adi Makmal
We developed a new quantum algorithm, termed QEMC, that is specifically designed for finding heuristic solutions for the MaxCut problem, a well-studied NP-hard combinatorial problem, with very few qubits. Our method uses a novel information encoding scheme that requires $log{N}$ qubits to address $N$-node graphs, an exponential reduction compared to QAOA. This significant qubit reduction results in shallower quantum circuits, which are more resistant to noise.
Strelniker Yakov
It is shown that when approaching the percolation threshold of a superconductor-insulator metamaterial, the critical temperature Tc can be significantly increased up to near-room temperature. This is due to the appearance of a negative permittivity near criticality. This yields electrons to experience attraction instead of repulsion, which leads the formation of Cooper electron pairs and, consequently, to superconductivity. The negative permittivity is found theoretically in the metal-dielectric superconducting metamaterial using the symmetric self-consistent effective medium approximation (SEMA) together with the Drude model of metal conductivity in the quasistatic limit. This negative permittivity value is substituted into the formula for the critical temperature, derived by the well accepted Ginzburg-Kirzhnits-Pashitskii theory which describes superconductivity in terms of permittivity where the concept of epsilon-near-zero (ENZ) has been employed. All analytical evaluations are exact within the framework of SEMA. We also provide a qualitative physical explanation for this theoretical prediction.
Amikam Levy
The invention provides a method for designing and implementing frequency-domain filter functions in quantum systems through dynamically invariant control fields. Unlike traditional dynamical decoupling methods, which derive spectral properties post hoc from time-domain sequences, this method analytically constructs time-dependent Hamiltonians that realize arbitrary spectral responses, including multi-band and phase-sensitive profiles. The approach utilizes the formalism of dynamical invariants to ensure exact state evolution and robustness to drive-amplitude errors. Experimental implementation on nitrogen-vacancy (NV) centers in diamond demonstrates enhanced coherence preservation and signal selectivity beyond conventional control protocols.
Stern Michael
See details in attached document.
Strelniker Yakov
We predicted that the negative permittivity can be used for attraction of like charged particles instead of repulsion. This can lead to creation of electron-electron pairs similar to Cooper pairs (with possibilities to reach superconductivity at room temperature). This phenomenon can be used also for nucleus-nucleus pairing with possibilities of low energy nuclear fusion. Negative values of permittivity we propose to achieve due to the localized surface plasmon resonances in metamaterials. These resonance frequencies can be varied over a wide range by application of static magnetic or electric fields.
Cohen Eliahu
Systems and methods are described for quantum information retrieval. An example system may include a quantum cloning unit, a photon number splitting (PNS) unit, and a weak measurement unit to enhance the accuracy and reliability of quantum state estimations without introducing substantial decoherence. The quantum cloning unit may be used to generate approximate clones of a qubit. If the qubit is a multi-photon state qubit, then the photon number splitting (PNS) unit may be used to intercept the multi-photon state qubit and reflect a single photon from the multi-photon state qubit, which may then be subjected to quantum cloning. These qubits and qubit clones may then be subjected to weak measurements, which provides detailed analysis with minimal disturbance to quantum properties such as superposition and entanglement.
Peer Avraham
A simple technique to generate cluster quantum states of light which are universal resources for quantum computing is disclosed. The technique uses two components. First, a broadband source of Einstein-Podolsky-Rosen entangled states, a.k.a. two-mode-squeezed states, generated in an optical frequency comb from a monochromatic pump field. Second, a phase modulator (typically by electro-optic effect) operating at frequencies multiple of the comb mode spacing. Using only these two components, cluster quantum states can be generated that have one-, two-, three-, or higher-dimensional graphs. The unprecedented compactness of this technique paves the way to implementing quantum computing on chip using quantum nanophotonics.
Cohen Eliahu
The proposed method enables to infer, with various degrees of disturbance, the information content of quantum channels. As a possible hacking and security analysis method it exposes and utilizes physical imperfections within common quantum key distribution protocols. It is based on noise injection followed by quantum weak measurements which allow to infer, to some extent, the bits of a distributed secret key. The method can be used for detecting and quantifying the severity of security vulnerabilities within quantum channels. As another application, the proposed method can monitor the performance and error rate of quantum computers.
Teman Adam
Embedded DRAM based FIFOs
