2013/09/30 by Juan Miguel Arrazola, Norbert Lütkenhaus · 1 citation
Computer Science · Mathematics · Physics and Astronomy · #Beam splitter #Coherent states #Computer science #Constant (computer programming) #Mathematics #Photon #Physics #Protocol (science) #Quantum #Quantum Computing Algorithms and Architecture #Quantum Information and Cryptography #Quantum Mechanics and Applications #Quantum mechanics #Quantum state #Qubit #Statistical physics #Superposition principle #TRACE (psycholinguistics) #quant-ph
paper · pdf · doi:10.1103/physreva.89.062305
published as Phys. Rev. A 89, 062305 (2014) · 5 pages, 2 Figures
openalex publication_date 2014/06/04 · arxiv created 2014/06/17 · arxiv updated 2014/06/19 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We present a protocol for quantum fingerprinting that is ready to be implemented with current technology and is robust to experimental errors. The basis of our scheme is an implementation of the signal states in terms of a coherent state in a superposition of time-bin modes. Experimentally, this requires only the ability to prepare coherent states of low amplitude and to interfere them in a balanced beam splitter. The states used in the protocol are arbitrarily close in trace distance to states of O(log2n) qubits, thus exhibiting an exponential separation in abstract communication complexity compared to the classical case. The protocol uses a number of optical modes that is proportional to the size n of the input bit strings but a total mean photon number that is constant and independent of n. Given the expended resources, our protocol achieves a task that is provably impossible using classical communication only. In fact, even in the presence of realistic experimental errors and loss, we show that there exist a large range of input sizes for which our quantum protocol transmits an amount of information that can be more than two orders of magnitude smaller than a classical fingerprinting protocol.