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Entanglement of high-dimensional multipartite systems plays an important role both in quantum foundation and applications of quantum physics. Inspired by the genuine high-dimensional entanglement (Kraft et al. in Phys Rev Lett 120:060502, 2018), we first propose a new criterion to characterize genuine entangled states in arbitrary finite dimensional systems. We further define two decomposable models by using embedding method for featuring experimentally untrusted parties. We show that the equivalence of local decomposability and embedded decomposability holds under special conditions for entangled pure states. For mixed states, we show the decomposability may be changed in embedded space. [ABSTRACT FROM AUTHOR]

The quantum adiabatic evolution is very important for quantum mechanics and applied in quantum information processing to solve the difficult problem. The traditional quantum adiabatic algorithms use the linear interpolating to construct quantum evolution paths. We construct special evolution paths to speedup quantum evolutions. By choosing state-dependent correlations some constant time evolution paths may be generated. This result is very useful quantum adiabatic simulations. [ABSTRACT FROM AUTHOR]

Quantum hidden problem being one of the most important quantum computation problems has been widely investigated. Our purpose in this paper is to prove the independent or partial independent of the reduced state derived from the quantum query with the oracle implementation. We prove that if without bias on implementation functions the subgroup state is independent of evaluation functions using the group representation. This result is also used to improve the quantum query success probability. [ABSTRACT FROM AUTHOR]

The quantum no-cloning theorem and no-deleting theorem may be the most important quantum features for quantum communications or quantum computations. In this paper, we concentrate typical properties of random quantum evolution. We obtain that universal random evolutions change the generic unknown pure states into their orthogonal states approximately. Moreover, typical random evolutions distort the von Neumann entropy with constants. These results are extended to mixed states with a stronger orthogonal preparation ability. These typical characters are very important for quantum information retrieving or various quantum tasks. [ABSTRACT FROM AUTHOR]

In this paper, we show that some special mixed quantum resource experience the same property of pure entanglement such as Bell state for quantum teleportation. It is shown that one mixed state and three bits of classical communication cost can be used to teleport one unknown qubit compared with two bits via pure resources. The schemes are easily implement with model physical techniques. Moreover, these resources are also optimal and typical for faithfully remotely prepare an arbitrary qubit, two-qubit and three-qubit states with mixed quantum resources. Our schemes are completed as same as those with pure quantum entanglement resources except only 1 bit additional classical communication cost required. The success probability is independent of the form of the mixed resources. [ABSTRACT FROM AUTHOR]

The critical merits acquired from quantum computation require running in parallel, which cannot be benefited from previous multi-level extensions and are exact our purposes. In this paper, with qutrit subsystems the general quantum computation further reduces into qutrit gates or its controlled operations. This extension plays parallizable and integrable with same construction independent of the qutrit numbers. The qutrit swapping as its basic operations for controlling can be integrated into quantum computers with present physical techniques. Our generalizations are free of elevating the system spaces, and feasible for the universal computation. [ABSTRACT FROM AUTHOR]

The cluster state has its feasibility for universal quantum computations. In this paper, we show that one symmetric cluster state can be used for the teleportation of an arbitrary two-qubit state deterministically. The one takes use of generalized Bell basis measurement while the other is completed using a general projective measurement from constructed orthogonal measurement basis and the Pauli flip measurement. Moreover, this state can also be utilized for remotely preparation of a restricted two qubit state within two different quantum network topologies, the controlled and jointed forms. Finally its capability for dense coding is investigated and shown n+3 classical bits transmissions by sending only n+1 qubits. [ABSTRACT FROM AUTHOR]

The main superiority of the quantum remote preparation over quantum teleportation lies the classical resource saving. This situation may be changed from the following constructions. Our purpose in this paper is to find some special differences between these two quantum tasks besides the classical resource costs. Some novel schemes show that the first one is useful to simultaneously broadcast arbitrary quantum states, while the second one cannot because of the quantum no-cloning theorem. Moreover, these broadcast schemes may be adapted to satisfying the different receivers' requirements or distributing the classical information, which are important in various quantum applications such as the quantum secret distribution or the quantum network communication. [ABSTRACT FROM AUTHOR]

Immeasurability of a quantum state has important consequence in practical implementation of quantum computers. Our purpose is to analyze the efficiency of the entangled output of Pati-Braunstein deleting machine or Wootters-Zurek quantum copying machine as a quantum channel. Interestingly we find that for special values of the input parameter the state does not violate the Bell's inequality. Moreover, we analyze the performances of the entangled output of Pati-Braunstein deleting after the Wootters-Zurek copying machine. [ABSTRACT FROM AUTHOR]

Our purpose in this paper, is to show that several senders can jointly prepare a five-qubit Brown-state to a remote receiver. By constructing some useful measurement bases, we first present two schemes to prepare an arbitrary Brown-state with real coefficients or complex coefficients via the same quantum channel. Then, by using the permutation group the success probability is improved. Finally, the present schemes are generalized to multi-sender. [ABSTRACT FROM AUTHOR]

By using a proper positive operator-valued measure (POVM), we present two new schemes for probabilistic transmission with non-maximally four-particle cluster states. In the first scheme, we demonstrate that two non-maximally four-particle cluster states can be used to realize probabilistically sharing an unknown three-particle GHZ-type state within either distant agent's place. In the second protocol, we demonstrate that a non-maximally four-particle cluster state can be used to teleport an arbitrary unknown multi-particle state in a probabilistic manner with appropriate unitary operations and POVM. Moreover the total success probability of these two schemes are also worked out. [ABSTRACT FROM AUTHOR]

Our purpose in this paper, is to show that several senders can jointly prepare a four-qubit | χ〉-state to a remote receiver. By constructing some useful measurement bases, we first present two schemes to prepare an arbitrary | χ〉-state with real coefficients or complex coefficients via the same quantum channel. Then, by using the permutation group the success probability is improved. Finally, the present schemes are generalized to multi-sender. [ABSTRACT FROM AUTHOR]

In this paper, we propose one quantum signature scheme with a weak arbitrator to sign classical messages. This scheme can preserve the merits in the original arbitrated scheme with some entanglement resources, and provide a higher efficiency in transmission and reduction the complexity of implementation. The arbitrator is costless and only involved in the disagreement case. [ABSTRACT FROM AUTHOR]

Motivated by some previous joint remote preparation schemes, we first propose some quantum circuits and photon circuits that two senders jointly prepare an arbitrary one-qubit state to a remote receiver via GHZ state. Then, by constructing KAK decomposition of some transformation in SO(4), one quantum circuit is constructed for jointly preparing an arbitrary two-qubit state to the remote receiver. Furthermore, some deterministic schemes of jointly preparing one-qubit and two-qubit states are presented. Besides, the proposed schemes are extended to multi-sender and the partially entangled quantum resources. [ABSTRACT FROM AUTHOR]

Quantum one-way functions play a fundamental role in cryptography because of its necessity for the secure encryption schemes taking into account the quantum computer. In this paper our purpose is to establish a theoretical framework for a candidate of the quantum one-way functions and quantum trapdoor functions based on one-parameter unitary groups. The dynamics of parameterized unitary groups ensure the one-wayness and quantum undistinguishability in different levels, and the physical feasibility are derived from the simultaneous approximation of its infinitesimal generators. Moreover, these special functions are used to construct new cryptosystems-the quantum public-key cryptosystems for encrypting both the classical and quantum information. [ABSTRACT FROM AUTHOR]

Complete active space self-consistent-field (CASSCF) and multiconfigurational second-order perturbation theory (CASPT2) calculations in conjunction with the ANO-L basis set were performed to investigate systematically the low-lying electronic states of HNCS and its ions in C symmetry. Our highly accurate calculation indicated that theoretically determined geometric parameters and harmonic vibrational frequencies for the ground-state XA′ are in good agreement with observed experimental data. The geometry of triplet HNCS is clearly favored C symmetry, and the relative energy is predicted to be 3.000 eV (69.2 kcal/mol). The vertical transition energies for the selected excited states of HNCS were calculated at CASSCF/CASPT2/ANO-L level of theory based on CASSCF optimized geometry. Except for a few linear states of XΠ (1A′, 1A″), 1Σ (1A″), and 1Σ (3A′) states of HNCS, our results confirmed that the majority of excited states are twisted trans-bend structures. The existence of bound excited anion states has been found for the first time in HNCS. A more elaborate examination of ionization potential of HNCS (AIP, VIP) than previous reports has been presented. [ABSTRACT FROM AUTHOR]

In this paper, we propose a scheme to remotely prepare an arbitrary two-qubit state from one sender to either of two receivers. Two cases of the prepared quantum state, an arbitrary two-qubit state with real coefficients and complex coefficients, are considered. Firstly, one single EPR pair and a GHZ state are used as the quantum channel. Then the present scheme is extended to some partially entangled states as the quantum channel. To design these schemes, some useful and general measurement bases have been constructed. The successful probability and classical communication cost of these schemes are also calculated to weigh the efficiency and cost. [ABSTRACT FROM AUTHOR]