Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:1306.5192

State Decoding in Multi-Stage Cryptography Protocols

Sindhu Chitikela

Published Jun 19, 2013• 0 citations
arXivHTMLPDF

Abstract

This paper presents a practical method of quantum tomography for decoding the state of photons in a multistage cryptography protocol. This method works if the polarization angles are defined on a fixed plane, as is assumed in several quantum cryptography protocols. We show if there are 2m polarization angles in a fixed plane, we need m number of filters and m2 number of photons through each filter.

DOI
10.48550/arxiv.1306.5192

Related papers

Methods to Counter Attacks on Quantum Cryptography Protocols

Sindhu Chitikela

The need for secure transmission in the fields of banking and defense has led to the interest in quantum cryptographic protocols which are theoretically more secure than any classical cryptographic protocol. However, the current implementations of the quantum cryptographic protocols have weaknesses. The main goal of this work is to find ways to strengthen quantum cryptographic protocols by using new implementation schemes. We present a method to improve the randomness of the sequence of polarization states used in BB84, the two-stage and the three-stage protocols. An analysis of quantum cryptography in the presence of noise is given. We also study a variant of the three-stage protocol where the intensity of the photons is tracked. We have developed a further improvement to this protocol where the state of the photons is also estimated.

•May 1, 2013•0 citations

Optimal Protocol for Polarization Ququart State Tomography

Ekaterina V. Moreva, A. K. Gavrichenko, Иван Владимирович Тихонов +1 more

We develop a practical quantum tomography protocol and implement measurements of pure states of ququarts realized with polarization states of photon pairs (biphotons). The method is based on an optimal choice of the measuring scheme’s parameters that provides better quality of reconstruction for the fixed set of statistical data. A high accuracy of the state reconstruction (above 0.99) indicates that developed methodology is adequate.

•Jan 1, 2009•0 citations

Optimal protocol for quantum state tomography

Ekaterina V. Moreva, Yu. I. Bogdanov, A. K. Gavrichenko +2 more

We develop a practical quantum tomography protocol and implement measurements of pure states of ququarts realized with polarization states of photon pairs (biphotons). The method is based on an optimal choice of the measuring scheme's parameters that provides better quality of reconstruction for the fixed set of statistical data. A high accuracy of the state reconstruction (above 0.99) indicates that developed methodology is adequate.

arXiv:0811.1927•Nov 12, 2008•0 citations

Tomography of multi-photon polarization states in conditions of non-unit quantum efficiency of detectors

Yu. I. Bogdanov, B. I. Bantysh, Nadezhda A. Bogdanova +1 more

Abstract Polarization multi-photon quantum state tomography with non-unit quantum efficiency of detectors is considered. A new quantum tomography protocol is proposed. This protocol considers the event of losing photons of a multi-photon quantum state in one or more channels among with n -fold coincidence events. The advantage of the proposed protocol compared with the standard n -fold coincidence protocol is demonstrated using methods of statistical analysis.

arXiv:1711.02964•Laser Physics•Jan 22, 2018•2 citations

Quantum-state tomography for optical polarization with arbitrary photon numbers

A. B. Klimov, José Luis Romero, Sascha Wallentowitz

A scheme for quantum-state tomography is presented that can be performed for polarized light with an arbitrary photon-number distribution. The proposed method fills the gap between existing polarization-tomography schemes for single-photon states and for optical fields with very large photon numbers. It consists of an optical homodyne setup triggered by the outcome of a single-photon counting module. The configuration space of polarization is parametrized by Euler angles and by an additional interference parameter, whose assessment requires conditional homodyne measurements.

Physical Review A•Feb 28, 2014•8 citations

Quantum secure communication using a multi-photon tolerant protocol

Mayssaa El Rifai, Pramode K. Verma

This paper proposes a quantum secure communication protocol using multiple photons to represent each bit of a message to be shared. The multi-photon tolerant approach to quantum cryptography provides a quantum level security while using more than a single photon per transmission. The protocol proposed is a multi-stage protocol; an explanation of its operation and implementation are provided. The multi-stage protocol is based on the use of unitary transformations known only to Alice and Bob. This paper studies the security aspects of the multi-stage protocol by assessing its vulnerability to different attacks. It is well known that as the number of photons increases, the level of vulnerability of the multi-stage protocol increases. This paper sets a limit on the number of photons that can be used while keeping the multi-stage protocol a multi-photon tolerant quantum secure method for communication. The analysis of the number of photons to be used is based on the probability of success of a Helstrom discrimination done by an eavesdropper on the channel. Limiting the number of photons up to certain threshold per stage makes it impossible for an eavesdropper to decipher the message sent over the channel. The proposed protocol obviates the disadvantages associated with single photon implementations, such as limited data rates and distances along with the need to have no more than a single photon per time slot. The multi-stage protocol is a step toward direct quantum communication rather than quantum key distribution associated with single photon approaches.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Mar 4, 2015•3 citations
This paper presents a practical method of quantum tomography for decoding the state of photons in a multistage cryptography protocol. This method works if the polarization angles are defined on a fixed plane, as is assumed in several quantum cryptography protocols. We show if there are 2m polarization angles in a fixed plane, we need m number of filters and m2 number of photons through each filter.
The need for secure transmission in the fields of banking and defense has led to the interest in quantum cryptographic protocols which are theoretically more secure than any classical cryptographic protocol. However, the current implementations of the quantum cryptographic protocols have weaknesses. The main goal of this work is to find ways to strengthen quantum cryptographic protocols by using new implementation schemes. We present a method to improve the randomness of the sequence of polarization states used in BB84, the two-stage and the three-stage protocols. An analysis of quantum cryptography in the presence of noise is given. We also study a variant of the three-stage protocol where the intensity of the photons is tracked. We have developed a further improvement to this protocol where the state of the photons is also estimated.
A scheme for quantum-state tomography is presented that can be performed for polarized light with an arbitrary photon-number distribution. The proposed method fills the gap between existing polarization-tomography schemes for single-photon states and for optical fields with very large photon numbers. It consists of an optical homodyne setup triggered by the outcome of a single-photon counting module. The configuration space of polarization is parametrized by Euler angles and by an additional interference parameter, whose assessment requires conditional homodyne measurements.
This paper proposes a quantum secure communication protocol using multiple photons to represent each bit of a message to be shared. The multi-photon tolerant approach to quantum cryptography provides a quantum level security while using more than a single photon per transmission. The protocol proposed is a multi-stage protocol; an explanation of its operation and implementation are provided. The multi-stage protocol is based on the use of unitary transformations known only to Alice and Bob. This paper studies the security aspects of the multi-stage protocol by assessing its vulnerability to different attacks. It is well known that as the number of photons increases, the level of vulnerability of the multi-stage protocol increases. This paper sets a limit on the number of photons that can be used while keeping the multi-stage protocol a multi-photon tolerant quantum secure method for communication. The analysis of the number of photons to be used is based on the probability of success of a Helstrom discrimination done by an eavesdropper on the channel. Limiting the number of photons up to certain threshold per stage makes it impossible for an eavesdropper to decipher the message sent over the channel. The proposed protocol obviates the disadvantages associated with single photon implementations, such as limited data rates and distances along with the need to have no more than a single photon per time slot. The multi-stage protocol is a step toward direct quantum communication rather than quantum key distribution associated with single photon approaches.