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Klaus Mølmer
Klaus Mølmer is a Danish physicist who is currently a professor at the Niels Bohr Institute of the University of Copenhagen. From 2000 to 2022, he was a professor of physics at the University of Aarhus. In 1999, Mølmer and Anders Sørensen proposed the Mølmer–Sørensen gate for trapped ion quantum computing, which was one of the first proposals for the implementation of a multi-qubit gate on a physical system. Mølmer was awarded the status of Fellow in the American Physical Society, after he was nominated by their Division of Atomic, Molecular & Optical Physics in 2008, for ''his outstanding and insightful contributions to theoretical quantum optics, quantum information science and quantum atom optics, including the development of novel computational methods to treat open systems in quantum mechanics and theoretical proposals for the quantum logic gates with trapped ions.'' See also * Entanglement depth *Quantum jump method *Mølmer–Sørensen gate In quantum comp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Danes
Danes ( da, danskere, ) are a North Germanic ethnic group and nationality native to Denmark and a modern nation identified with the country of Denmark. This connection may be ancestral, legal, historical, or cultural. Danes generally regard themselves as a nationality and reserve the word "ethnic" for the description of recent immigrants, sometimes referred to as "new Danes". The contemporary Danish national identity is based on the idea of "Danishness", which is founded on principles formed through historical cultural connections and is typically not based on racial heritage. History Early history Denmark has been inhabited by various Germanic peoples since ancient times, including the Angles, Cimbri, Jutes, Herules, Teutones and others. The first mentions of " Danes" are recorded in the mid-6th century by historians Procopius ( el, δάνοι) and Jordanes (''danī''), who both refer to a tribe related to the Suetidi inhabiting the peninsula of Jutland, the province of Sc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Niels Bohr Institute
The Niels Bohr Institute (Danish: ''Niels Bohr Institutet'') is a research institute of the University of Copenhagen. The research of the institute spans astronomy, geophysics, nanotechnology, particle physics, quantum mechanics and biophysics. Overview The institute was founded in 1921, as the Institute for Theoretical Physics of the University of Copenhagen, by the Danish theoretical physicist Niels Bohr, who had been on the staff of the University of Copenhagen since 1914, and who had been lobbying for its creation since his appointment as professor in 1916. On the 80th anniversary of Niels Bohr's birth – October 7, 1965 – the Institute officially became the Niels Bohr Institute. Much of its original funding came from the charitable foundation of the Carlsberg brewery, and later from the Rockefeller Foundation. During the 1920s, and 1930s, the institute was the center of the developing disciplines of atomic physics and quantum physics. Physicists from across Europe (and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University Of Copenhagen
The University of Copenhagen ( da, Københavns Universitet, KU) is a prestigious public university, public research university in Copenhagen, Copenhagen, Denmark. Founded in 1479, the University of Copenhagen is the second-oldest university in Scandinavia after Uppsala University, and ranks as one of the top universities in the Nordic countries, Europe and the world. Its establishment sanctioned by Pope Sixtus IV, the University of Copenhagen was founded by Christian I of Denmark as a Catholic teaching institution with a predominantly Theology, theological focus. In 1537, it was re-established by King Christian III as part of the Lutheran Reformation. Up until the 18th century, the university was primarily concerned with educating clergymen. Through various reforms in the 18th and 19th century, the University of Copenhagen was transformed into a modern, Secularism, secular university, with science and the humanities replacing theology as the main subjects studied and taught. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University Of Aarhus
Aarhus University ( da, Aarhus Universitet, abbreviated AU) is a public research university with its main campus located in Aarhus, Denmark. It is the second largest and second oldest university in Denmark. The university is part of the Coimbra Group, the Guild, and Utrecht Network of European universities and is a member of the European University Association. The university was founded in Aarhus, Denmark, in 1928 and comprises five faculties in Arts, Natural Sciences, Technical Sciences, Health, and Business and Social Sciences and has a total of twenty-seven departments. It is home to over thirty internationally recognised research centres, including fifteen centres of excellence funded by the Danish National Research Foundation. The university has been ranked among the top 100 world's best universities. ''Times Higher Education'' ranks Aarhus University in the top 10 of the most beautiful universities in Europe (2018). The university's alumni include Bjarne Stroustrup, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mølmer–Sørensen Gate
In quantum computing, Mølmer–Sørensen gate scheme (or MS gate) refers to an implementation procedure for various multi- qubit quantum logic gates used mostly in trapped ion quantum computing. This procedure is based on the original proposition by Klaus Mølmer and Anders Sørensen in 1999-2000. This proposal was an alternative to the 1995 Cirac–Zoller controlled-NOT gate implementation for trapped ions, which requires that the system be restricted to the joint motional ground state of the ions. In an MS gate, entangled states are prepared by illuminating ions with a bichromatic light field. Mølmer and Sørensen identified two regimes in which this is possible: # A weak-field regime, where single-photon absorption is suppressed and two-photon processes interfere in a way that makes internal state dynamics insensitive to the vibrational state # A strong-field regime where the individual ions are coherently excited, and the motional state is highly entangled with the inte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trapped Ion Quantum Computing
A trapped-ion quantum computer is one proposed approach to a large-scale quantum computer. Ions, or charged atomic particles, can be confined and suspended in free space using electromagnetic fields. Qubits are stored in stable electronic states of each ion, and quantum information can be transferred through the collective quantized motion of the ions in a shared trap (interacting through the Coulomb force). Lasers are applied to induce coupling between the qubit states (for single qubit operations) or coupling between the internal qubit states and the external motional states (for entanglement between qubits). The fundamental operations of a quantum computer have been demonstrated experimentally with the currently highest accuracy in trapped-ion systems. Promising schemes in development to scale the system to arbitrarily large numbers of qubits include transporting ions to spatially distinct locations in an array of ion traps, building large entangled states via photonicall ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American Physical Society
The American Physical Society (APS) is a not-for-profit membership organization of professionals in physics and related disciplines, comprising nearly fifty divisions, sections, and other units. Its mission is the advancement and diffusion of knowledge of physics. The society publishes more than a dozen scientific journals, including the prestigious '' Physical Review'' and ''Physical Review Letters'', and organizes more than twenty science meetings each year. APS is a member society of the American Institute of Physics. Since January 2021 the organization has been led by chief executive officer Jonathan Bagger. History The American Physical Society was founded on May 20, 1899, when thirty-six physicists gathered at Columbia University for that purpose. They proclaimed the mission of the new Society to be "to advance and diffuse the knowledge of physics", and in one way or another the APS has been at that task ever since. In the early years, virtually the sole activity of the AP ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quantum Optics
Quantum optics is a branch of atomic, molecular, and optical physics dealing with how individual quanta of light, known as photons, interact with atoms and molecules. It includes the study of the particle-like properties of photons. Photons have been used to test many of the counter-intuitive predictions of quantum mechanics, such as entanglement and teleportation, and are a useful resource for quantum information processing. History Light propagating in a restricted volume of space has its energy and momentum quantized according to an integer number of particles known as photons. Quantum optics studies the nature and effects of light as quantized photons. The first major development leading to that understanding was the correct modeling of the blackbody radiation spectrum by Max Planck in 1899 under the hypothesis of light being emitted in discrete units of energy. The photoelectric effect was further evidence of this quantization as explained by Albert Einstein in a 1905 paper ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quantum Information Science
Quantum information science is an interdisciplinary field that seeks to understand the analysis, processing, and transmission of information using quantum mechanics principles. It combines the study of Information science with quantum effects in physics. It includes theoretical issues in computational models and more experimental topics in quantum physics, including what can and cannot be done with quantum information. The term quantum information theory is also used, but it fails to encompass experimental research, and can be confused with a subfield of quantum information science that addresses the processing of quantum information. Scientific and engineering studies To understand quantum teleportation, quantum entanglement and the manufacturing of quantum computer hardware requires a thorough understanding of quantum physics and engineering. Since 2010s, there has been remarkable progress in manufacturing quantum computers, with companies like Google and IBM investing heavily ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quantum Mechanics
Quantum mechanics is a fundamental theory in physics that provides a description of the physical properties of nature at the scale of atoms and subatomic particles. It is the foundation of all quantum physics including quantum chemistry, quantum field theory, quantum technology, and quantum information science. Classical physics, the collection of theories that existed before the advent of quantum mechanics, describes many aspects of nature at an ordinary (macroscopic) scale, but is not sufficient for describing them at small (atomic and subatomic) scales. Most theories in classical physics can be derived from quantum mechanics as an approximation valid at large (macroscopic) scale. Quantum mechanics differs from classical physics in that energy, momentum, angular momentum, and other quantities of a bound system are restricted to discrete values ( quantization); objects have characteristics of both particles and waves (wave–particle duality); and there are limits to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Entanglement Depth
In quantum physics, entanglement depth characterizes the strength of multiparticle entanglement. An entanglement depth k means that the quantum state of a particle ensemble cannot be described under the assumption that particles interacted with each other only in groups having fewer than k particles. It has been used to characterize the quantum states created in experiments with cold gases. Definition Entanglement depth appeared first in the context of cold gases, together with entanglement criteria that made it possible to bound it from below based on measured quantities. We will now present a general definition based on convex sets of quantum states. First, we will define k-producibility. Let us consider a pure state that is the tensor product In mathematics, the tensor product V \otimes W of two vector spaces and (over the same field) is a vector space to which is associated a bilinear map V\times W \to V\otimes W that maps a pair (v,w),\ v\in V, w\in W to an elemen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quantum Jump Method
The quantum jump method, also known as the Monte Carlo method, Monte Carlo wave function (MCWF) is a technique in computational physics used for simulating open quantum systems and quantum dissipation. The quantum jump method was developed by Jean Dalibard, Dalibard, Castin and Klaus Mølmer, Mølmer at a similar time to the similar method known as Quantum Trajectory Theory developed by Howard Carmichael, Carmichael. Other contemporaneous works on wave-function-based Monte Carlo method, Monte Carlo approaches to open quantum systems include those of Dum, Peter Zoller, Zoller and Helmut Ritsch, Ritsch and Hegerfeldt and Wilser.The associated primary sources are, respectively: * * * * Method The quantum jump method is an approach which is much like the Lindblad equation, master-equation treatment except that it operates on the wave function rather than using a density matrix approach. The main component of this method is evolving the system's wave function in time with a pseudo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
