arXiv subjects

Chia-Wei Tsai

Publications and source records attributed to Chia-Wei Tsai.

12 recordsLinked to original sources

arXiv2026

GHZ-Equivalent State Distribution in Quantum Networks: Reducing Decoherence and Quantum Resource Consumption

This study proposes a novel scheme for distributing GHZ-equivalent states across repeater-based quantum networks, with particular focus on the analysis and mitigation of decoherence effects during transmission. The proposed scheme enables remote users to share graph states, which can be leveraged to implement various quantum communication protocols, such as quantum key distribution and quantum secret sharing. Compared with existing approaches, the proposed distributed scheme requires only O(N) qubits without introducing redundant entanglement structures. Together with the linear-scaling merging procedure in both controlled gate count and qubit usage, the proposed framework supports more efficient large-scale graph state distribution. To evaluate its feasibility and correctness, this study utilizes the quantum network simulation tool, NetSquid, to implement the proposed scheme. Simulation results demonstrate that the proposed approach is both effective and practical for executing quantum communication protocols within quantum networks.

quant-ph↗

arXiv2021

Multiparty Mediated Quantum Secret Sharing Protocol

This study proposes a multiparty mediated quantum secret sharing (MQSS) protocol that allows n restricted quantum users to share a secret via the assistance of a dishonest third-party (TP) with full quantum capabilities. Under the premise that a restricted quantum user can only perform the Hadamard transformation and the Z-basis measurement, the proposed MQSS protocol has addressed two common challenges in the existing semi-quantum secret sharing protocols: (1) the dealer must have full quantum capability, and (2) the classical users must equip with the wavelength quantum filter and the photon number splitters (PNS) to detect the Trojan horse attacks. The security analysis has also delivered proof to show that the proposed MQSS protocol can avoid the collective attack, the collusion attack, and the Trojan horse attacks. In addition, the proposed MQSS protocol is more efficient than the existing SQSS protocols due to the restricted quantum users can only equip with two quantum operations, and the qubits are transmitted within a shorter distance.

cs.CR↗

arXiv2021

Lightweight Mediated Semi-Quantum Key Distribution Protocol with a Dishonest Third Party based on Bell States

The mediated semi-quantum key distribution (MSQKD) protocol is an important research issue that lets two classical participants share secret keys securely between each other with the help of a third party (TP). However, in the existing MSQKD protocols, there are two improvable issues, namely (1) the classical participants must be equipped with expensive detectors to avoid Trojan horse attacks and (2) the trustworthiness level of TP must be honest. To the best of our knowledge, none of the existing MSQKD protocols can resolve both these issues. Therefore, this study takes Bell states as the quantum resource to propose a MSQKD protocol, in which the classical participants do not need a Trojan horse detector and the TP is dishonest. Furthermore, the proposed protocol is shown to be secure against well-known attacks and the classical participants only need two quantum capabilities. Therefore, in comparison to the existing MSQKD protocols, the proposed protocol is better practical.

quant-ph↗

arXiv2021

Lightweight Mediated Semi-Quantum Secret Sharing Protocol

Due to the exiting semi-quantum secret sharing protocol have two challenges including (1) the dealer must be the quantum user, and (2) the classical users must equip with the Trojan Horse detectors, this study wants to propose a novel mediate semi-quantum secret sharing (MSQSS) protocol to let a classical dealer can share his/her secrets to the classical agents with the help of a dishonest third-party (TP). The proposed MSQSS protocol adopts the one-way quantum communication and thus it is free from the Trojan Horse attacks. Furthermore, the security analysis is given for proving that the proposed protocol can be against the collective attack. Comparing to the exiting SQSS protocols, the proposed MSQSS protocol is more lightweight and more practical.

quant-ph↗

arXiv2020

Lightweight Quantum Security Protocols

Inspired by the semi-quantum protocols, this paper defines the lightweight quantum security protocols, in which lightweight participants can only operate two out of four very lightweight quantum operations. Subsequently, this study proposes a Lightweight Mediated Quantum Key Distribution (LMQKD) protocol as an example to disclose the feasibility and advantage of the lightweight quantum protocol. In the proposed protocol, a dishonest third party (TP) with complete quantum capabilities helps two lightweight quantum users establish a secure key. The lightweight quantum users are allowed to perform only: (1) unitary operations and (2) reflecting qubits without disturbance. The proposed protocol has been showed to be robust under the collective attack.

quant-ph↗

arXiv2020

Mediated semi-quantum key distribution in randomization-based environment

This paper proposes the first mediated semi-quantum key distribution in randomization-based environment with an untrusted third party(TP) who has the complete quantum capabilities to help two classical users to establish a secure key. The entanglement swapping between the collapsed qubits of Bell states and the Bell states is used to facilitate the design of the RSQKD protocol.

quant-ph↗

arXiv2020

Quantum Key Recycling with Optimal Key Recycling Rate based on Error Rate

We propose a new Quantum Key Recycling (QKR) protocol, which can tolerate the noise in the quantum channel. Our QKR protocol recycles the used keys according to the error rate. The key recycling rate of the pre-shared keys in our QKR protocol is optimized depending on the real error rate in the quantum channel. And our QKR protocol has higher efficiency than the exiting QKR protocol with error-tolerance. The security proof shows the security of the recycled keys is universal composable.

quant-ph↗

arXiv2020

Quantum Key Recycling can share key more efficient than BB84

We calculate the key sharing rate of Lu et al.'s Quantum Key Recycling (QKR) protocol. The key sharing rate is another version of the key rate, but it can be calculated for both the Quantum Key Distribution (QKD) protocols and the QKR protocols. We define the key sharing rate in this study and compare the key sharing rate of the QKR protocol to the rate of the QKD protocols. We found Lu et al.'s QKR protocol can be used to share keys more efficiently than BB84 in some situations. We also compare the six-state version of Lu et al.'s QKR protocol to the six-state QKD protocol. The results of this study show the potential advantages of using pre-shared keys to replace the public discussion in quantum protocols.

quant-ph↗

arXiv2015

Thermoelectric effects of quantum dot arrays embedded in nanowires

The thermoelectric properties of quantum dot arrays (QDAs) embedded in nanowires connected to electrodes are studied theoretically in the Coulomb blockade regime. A Hurbbard-Anderson model is used to simulate the electronic contribution to thermoelectric proper- ties of a QDA junction system. The electrical conductance, Seebeck coefficient, and electron thermal conductance are calculated by both the Keldysh Green function method and the mean-field approach. The phonon thermal conductivities are calculated by using the equation of phonon radiative transfer method. In the Coulomb blockade regime the electron thermal conductance is much smaller than the phonon thermal conductance. Therefore, the optimal figure of merit (ZT) can be enhanced by increasing thermal power and decreasing phonon thermal conductance simultaneously. We found that it is possible to obtain ZT value of InGaAs/GaAs QDAs embedded in nanowires larger than one at room temperature.

cond-mat.mes-hall↗

arXiv2012

Quantum Teleportation with Remote Rotation on a GHZ state

This study proposes a pioneering protocol for teleporting an arbitrary single particle state and simultaneously performing a rotation operation on that particle. There are protocols for either only teleporting particles or only remotely controlling quantum particles. If one has to remotely control a teleported quantum, then he/she has to first do the quantum teleportation and then perform the remote control on the teleported quantum. Both operations were done separately on two sets of entanglements. However, this intuitive solution is inefficient because many resources are wasted. Therefore, the study attempts to complete both operations using only one Greenberger-Horne-Zeilinger (GHZ) state.

quant-ph↗

arXiv2011

Comment on "Semiquantum secret sharing using entangled states"

Recently, Li et al. [Phys. Rev. A, 82(2), 022303] presented two semi-quantum secret sharing (SQSS) protocols using GHZ-like states. The proposed schemes are rather practical because only the secret dealer requires to equip with advanced quantum devices such as quantum memory, whereas the other agents can merely perform classical operations to complete the secret sharing. However, this study points out that a security pitfall exists in the eavesdropping check phase of both schemes that could mount to an Intercept-resend attack and a Trojan horse attack on the two schemes, respectively, to disclose the other agent's shadow, and further to reveal the master key of the SQSS, which contradicts to the security requirement of a QSS. Fortunately, two possible solutions are proposed to avoid this security pitfall.

quant-ph↗

arXiv2011

Quantum Secret Authentication Code

This study proposes a quantum secret authentication code for protecting the integrity of secret quantum states. Since BB84[1] was first proposed, the eavesdropper detection strategy in almost all quantum cryptographic protocols is based on the random sample discussion, in which the probability of eavesdropper detection is depending on the number of check qubits eavesdropped by the eavesdropper. Hence, if the eavesdropper interferes only a few qubits of the transmitted quantum sequence, then the detection probability will be very low. This study attempts to propose a quantum secret authentication code to solve this problem. With the use of quantum secret authentication code, not only is the probability of eavesdropper detection guaranteed to be evenly distributed no matter how many qubits had been eavesdropped, but also can the quantum transmission efficiency be highly enhanced.

quant-ph↗