30 research outputs found
A Hybrid Quantum-Classical Generative Adversarial Network for Near-Term Quantum Processors
In this article, we present a hybrid quantum-classical generative adversarial
network (GAN) for near-term quantum processors. The hybrid GAN comprises a
generator and a discriminator quantum neural network (QNN). The generator
network is realized using an angle encoding quantum circuit and a variational
quantum ansatz. The discriminator network is realized using multi-stage
trainable encoding quantum circuits. A modular design approach is proposed for
the QNNs which enables control on their depth to compromise between accuracy
and circuit complexity. Gradient of the loss functions for the generator and
discriminator networks are derived using the same quantum circuits used for
their implementation. This prevents the need for extra quantum circuits or
auxiliary qubits. The quantum simulations are performed using the IBM Qiskit
open-source software development kit (SDK), while the training of the hybrid
quantum-classical GAN is conducted using the mini-batch stochastic gradient
descent (SGD) optimization on a classic computer. The hybrid quantum-classical
GAN is implemented using a two-qubit system with different discriminator
network structures. The hybrid GAN realized using a five-stage discriminator
network, comprises 63 quantum gates and 31 trainable parameters, and achieves
the Kullback-Leibler (KL) and the Jensen-Shannon (JS) divergence scores of 0.39
and 4.16, respectively, for similarity between the real and generated data
distributions
On classical n-absorbing submodules
In this paper, we introduce the notion of classical n-absorbing submodules of a module M over a commutative ring R with identity, which is a generalization of classical prime submodules. A proper submodule N of M is said to be classical n-absorbing if whenever a1a2... an+1 m in M, for a1a2... an+1 in R and m in M, then there are n of the ai's whose product with m is in N. We give some basic results concerning classical n-absorbing submodules. Then the classical n-absorbing avoidance theorem for submodules is proved. Finally, classical n-absorbing submodules in several classes of modules are studied
CMOS Quantum Computing: Toward A Quantum Computer System-on-Chip
Quantum computing is experiencing the transition from a scientific to an
engineering field with the promise to revolutionize an extensive range of
applications demanding high-performance computing. Many implementation
approaches have been pursued for quantum computing systems, where currently the
main streams can be identified based on superconducting, photonic, trapped-ion,
and semiconductor qubits. Semiconductor-based quantum computing, specifically
using CMOS technologies, is promising as it provides potential for the
integration of qubits with their control and readout circuits on a single chip.
This paves the way for the realization of a large-scale quantum computing
system for solving practical problems. In this paper, we present an overview
and future perspective of CMOS quantum computing, exploring developed
semiconductor qubit structures, quantum gates, as well as control and readout
circuits, with a focus on the promises and challenges of CMOS implementation
When the annihilator graph of a commutative ring is planar or toroidal?
Let R be a commutative ring with identity, and let Z(R) be the set of zero-divisors of R. The annihilator graph of R is defined as the undirected graph AG(R) with the vertex set Z(R)* = Z(R) \ {0}, and two distinct vertices x and y are adjacent if and only if ann_R(xy) \neq ann_R(x) \cup ann_R(y). In this paper, all rings whose annihilator graphs can be embedded on the plane or torus are classified
Some classes of perfect strongly annihilating-ideal graphs associated with commutative rings
summary:Let be a commutative ring with identity and be the set of ideals with nonzero annihilator. The strongly annihilating-ideal graph of is defined as the graph with the vertex set and two distinct vertices and are adjacent if and only if and . In this paper, the perfectness of for some classes of rings is investigated
The annihilating-ideal graph of z(n) is weakly perfect
A graph is called weakly perfect if its vertex chromatic number equals its clique number. Let RR be a commutative ring with identity and A(R)A(R) be the set of ideals with non-zero annihilator. The annihilating-ideal graph of RR is defined as the graph AG(R)AG(R) with the vertex set A(R)∗=A(R)∖{0}A(R)∗=A(R)∖{0} and two distinct vertices II and JJ are adjacent if and only if IJ=0IJ=0. In this paper, we show that the graph AG(Zn)AG(Zn), for every positive integer nn, is weakly perfect. Moreover, the exact value of the clique number of AG(Zn)AG(Zn) is given and it is proved that AG(Zn)AG(Zn) is class 1 for every positive integer nn
Signature of Non-Minimal Scalar-Gravity Coupling with an Early Matter Domination on the Power Spectrum of Gravitational Waves
The signal strength of primordial gravitational waves experiencing an epoch
of early scalar domination is reduced with respect to radiation domination. In
this paper, we demonstrate that the specific pattern of this reduction is
sensitive to the coupling between the dominant field and gravity. When this
coupling is zero, the impact of early matter domination on gravitational waves
is solely attributed to the alteration of the Hubble parameter and the scale
factor. In the presence of non-zero couplings, on the other hand, the evolution
of primordial gravitational waves is directly affected as well, resulting in a
distinct step-like feature in the power spectrum of the gravitational wave as a
function of frequency. This feature serves as a smoking gun signature of this
model. In this paper, we provide an analytical expression of the power spectrum
that illustrates the dependence of power spectrum on model parameters and
initial conditions. Furthermore, we provide analytical relations that specify
the frequency interval in which the step occurs. We compare the analytical
estimates with numerical analysis and show they match well.Comment: 19 pages, 7 figures, 1 table, and 2 appendice
GaN Integrated Circuit Power Amplifiers: Developments and Prospects
GaN integrated circuit technologies have dramatically progressed over the recent years. The prominent feature of GaN high-electron mobility transistors (HEMTs), unparalleled output power densities, has created a paradigm shift in the established and emerging high-power applications. In this article, we present a review on the developments and prospects of GaN integrated circuit power amplifiers (PAs). The progress of GaN transistors including improvements in their important features, i.e., supply voltage, substrate material, transistor scaling approach, and device modeling are elaborated and the current state-of-the-art processes with 20-nm gate length, 450 GHz cut-off frequency, and over 600 V supply voltage are discussed. We also investigate developments in the GaN integrated circuit PA architectures and their implementation challenges including the reactive matching PAs capable of delivering over 100 W output power and operating up to 200 GHz, PA linearity, back-off efficiency enhancement, reconfigurable PAs, and distributed PA architectures. Finally, we discuss the prospects of GaN technology and possible future improvements, in transistor and circuit levels, which can advance performance and functionality of GaN integrated circuits
A note on infinite -groups
summary:Let be a group. If every nontrivial subgroup of has a proper supplement, then is called an -group. We study some properties of -groups. For instance, it is shown that a nilpotent group is an -group if and only if is a subdirect product of cyclic groups of prime orders. We prove that if is an -group which satisfies the descending chain condition on subgroups, then is finite. Among other results, we characterize all abelian groups for which every nontrivial quotient group is an -group. Finally, it is shown that if is an -group and , where and are primes, then has a triple factorization