Creating and Detecting Micro-Macro Photon
... entangled photon pair, we propose to start from a singlephoton entangled state, which can be created by sending a single photon onto a beam splitter [16–19]. The presence of single-photon entanglement can be proven experimentally by homodyne tomography [17], and also by a combination of interference ...
... entangled photon pair, we propose to start from a singlephoton entangled state, which can be created by sending a single photon onto a beam splitter [16–19]. The presence of single-photon entanglement can be proven experimentally by homodyne tomography [17], and also by a combination of interference ...
Quantum Phase Transitions - Subir Sachdev
... The simple considerations of Section 2 have given a rather complete description (based on the quasiparticle picture) of the physics for g ¿ gc and g À gc . We turn, finally, to the region g ≈ gc . For the specific models discussed in Section 2, a useful description is obtained by a method that is a ...
... The simple considerations of Section 2 have given a rather complete description (based on the quasiparticle picture) of the physics for g ¿ gc and g À gc . We turn, finally, to the region g ≈ gc . For the specific models discussed in Section 2, a useful description is obtained by a method that is a ...
Read PDF - Physics
... where neither a classical wave evolution description nor a single particle quantum wave description can provide an explanation. One challenging proposal is to perform the same interference experiment with neutrons. A conceptually different approach aiming to find out where the particles were inside ...
... where neither a classical wave evolution description nor a single particle quantum wave description can provide an explanation. One challenging proposal is to perform the same interference experiment with neutrons. A conceptually different approach aiming to find out where the particles were inside ...
PDF
... proposed GHZ quantum communication system: one using dual degenerate parametric amplifiers (dual-DPAs) for its entanglement source, and the other using a DPA plus a heralded source of single photons. We show that the density operators of the entangled mixed states stored in the quantum memories are d ...
... proposed GHZ quantum communication system: one using dual degenerate parametric amplifiers (dual-DPAs) for its entanglement source, and the other using a DPA plus a heralded source of single photons. We show that the density operators of the entangled mixed states stored in the quantum memories are d ...
notes #1 - U of L Class Index
... example, if you take five steps in a particular direction that could be described as taking “one step in that direction five times”. The one step is the vector, doing it five times is multiplying the vector by the scalar number, five. The result is a vector of magnitude five in some direction. This ...
... example, if you take five steps in a particular direction that could be described as taking “one step in that direction five times”. The one step is the vector, doing it five times is multiplying the vector by the scalar number, five. The result is a vector of magnitude five in some direction. This ...
On beating the hybrid argument
... The complexity classes we consider are certain “low” complexity classes between AC 0 and L. We show that the hybrid loss can indeed be avoided entirely when Z is obtained by repeated sampling from the distribution (U, f (U )), for hard functions f that enjoy a special type of random self-reducibilit ...
... The complexity classes we consider are certain “low” complexity classes between AC 0 and L. We show that the hybrid loss can indeed be avoided entirely when Z is obtained by repeated sampling from the distribution (U, f (U )), for hard functions f that enjoy a special type of random self-reducibilit ...
Quantum Operating Systems - Henry Corrigan
... The last few years have seen tremendous progress towards the construction of non-trivial quantum computers [7, 23, 29]. A number of start-ups are working towards commercializing the technology, NIST is standardizing new “post-quantum” cryptosystems [41], and industry giants, including Google [20] an ...
... The last few years have seen tremendous progress towards the construction of non-trivial quantum computers [7, 23, 29]. A number of start-ups are working towards commercializing the technology, NIST is standardizing new “post-quantum” cryptosystems [41], and industry giants, including Google [20] an ...
EQUILIBRIUM STATE OF A SELF
... purpose because if a de Sitter invariant state is constructed in a part of the space-time, it may be analytically continued to the whole space-time. As a rst step to the understanding of the behaviour of the interacting scalar eld (1) in the de Sitter background, let us calculate the evolution of ...
... purpose because if a de Sitter invariant state is constructed in a part of the space-time, it may be analytically continued to the whole space-time. As a rst step to the understanding of the behaviour of the interacting scalar eld (1) in the de Sitter background, let us calculate the evolution of ...
The Limits of Quantum Computers
... to be either spinning up or spinning down. For our purposes, what it means for a particle to spin up or down is irrelevant; all that matters is that there is some property of the particle that has one of two values when measured. To describe the quantum state of this collection of particles, one mus ...
... to be either spinning up or spinning down. For our purposes, what it means for a particle to spin up or down is irrelevant; all that matters is that there is some property of the particle that has one of two values when measured. To describe the quantum state of this collection of particles, one mus ...
Quantum scattering
... Furthermore, in both versions of the Krein-Friedel-Lloyd formulas the energy argument E + iη can be replaced by the wavenumber argument k + iη′ . These expressions only make sense for wavenumbers on or above the real k-axis. In particular, if k is chosen to be real, η′ must be greater than zero. Oth ...
... Furthermore, in both versions of the Krein-Friedel-Lloyd formulas the energy argument E + iη can be replaced by the wavenumber argument k + iη′ . These expressions only make sense for wavenumbers on or above the real k-axis. In particular, if k is chosen to be real, η′ must be greater than zero. Oth ...
Research Statement
... apply to experimentally realistic parameter regimes (see e.g., [11, 18, 19, 20, 21]). To model experimental error, one would at least want an “approximate hardness” result ruling out efficient classical sampling from any distribution close in total variation distance to the ideal quantum distributio ...
... apply to experimentally realistic parameter regimes (see e.g., [11, 18, 19, 20, 21]). To model experimental error, one would at least want an “approximate hardness” result ruling out efficient classical sampling from any distribution close in total variation distance to the ideal quantum distributio ...
Quantum mechanical computers | SpringerLink
... elements to be put together. Besides this total sum, the total of the three, a, b, and c and the carry, we obtain on the other two lines two pieces of information. One is the a that we started with, and the other is some intermediary quantity that we calculated on route. This is typical of these rev ...
... elements to be put together. Besides this total sum, the total of the three, a, b, and c and the carry, we obtain on the other two lines two pieces of information. One is the a that we started with, and the other is some intermediary quantity that we calculated on route. This is typical of these rev ...
Decoherence and the Transition from Quantum to Classical–Revisited
... we do know the possible alternatives, and we can safely act as if only one of those alternatives has occurred. As we shall see in the next section, such an assumption is not only unsafe but also simply wrong for a system described by |Φc i. How then can an observer (who has not yet consulted the det ...
... we do know the possible alternatives, and we can safely act as if only one of those alternatives has occurred. As we shall see in the next section, such an assumption is not only unsafe but also simply wrong for a system described by |Φc i. How then can an observer (who has not yet consulted the det ...
Coherent State Path Integrals
... that the number of bosons is a globally conserved quantity, which is why one is allowed to introduce a chemical potential, i.e. to use the Grand Canonical Ensemble in the first place. This formulation is useful to study superfluid Helium and similar problems. Suppose for instance that we want to com ...
... that the number of bosons is a globally conserved quantity, which is why one is allowed to introduce a chemical potential, i.e. to use the Grand Canonical Ensemble in the first place. This formulation is useful to study superfluid Helium and similar problems. Suppose for instance that we want to com ...
Probability amplitude
In quantum mechanics, a probability amplitude is a complex number used in describing the behaviour of systems. The modulus squared of this quantity represents a probability or probability density.Probability amplitudes provide a relationship between the wave function (or, more generally, of a quantum state vector) of a system and the results of observations of that system, a link first proposed by Max Born. Interpretation of values of a wave function as the probability amplitude is a pillar of the Copenhagen interpretation of quantum mechanics. In fact, the properties of the space of wave functions were being used to make physical predictions (such as emissions from atoms being at certain discrete energies) before any physical interpretation of a particular function was offered. Born was awarded half of the 1954 Nobel Prize in Physics for this understanding (see #References), and the probability thus calculated is sometimes called the ""Born probability"". These probabilistic concepts, namely the probability density and quantum measurements, were vigorously contested at the time by the original physicists working on the theory, such as Schrödinger and Einstein. It is the source of the mysterious consequences and philosophical difficulties in the interpretations of quantum mechanics—topics that continue to be debated even today.