ID Quantique
description
Transcript of ID Quantique
Economic Stimulus: Valorization of Single Photon Detectors and Quantum Key
Distribution Systems
Hugo Zbinden
Group of Applied Physics (GAP), UNIGE
NCCR Transfert Projects (GAP – id Quantique):High Speed Single Photon Counting Module (H.Z.)
Second Generation QKD Engine (N. Gisin)
ID Quantique
Encryption Business Unit InstrumentationBusiness Unit
• Spin-off from GAP based in Geneva• Founded in 2001• 17 employees ( 4 from GAP)• Customer base on 6 continents
Technology
- Single-photon detectors
Two product lines- High-Speed Encryption- Quantum Cryptography RNG Business Unit
Services(training, installation, maintenance)
3 business units
NCCR-QP Project 4:Single Photon Detectors
1. InGaAs Avalanche photon detectors2. Supraconducting Detectors3. Hybrid schemes: Upconversion detectors, photon number resolving etc
Performance:
= 10-20%
Pdark = 1000/s
Timing jitter = 300 ps
Max. Rate = 100 kHz
Si-APD:
50 %
cdark = 10/s
50 ps
10 MHz
InGaAs Avalanche Photo Diode
U
IU B ias
Afterpulsing is a problem
Mitigation: - deadtime- rapid quenching or short gates
-> limited count rate, duty cycle < 1
t
U B ias
U B reak do w n
Sinus gating allows high count rates
Pulse rate 1.25 GHz, gate width ~130ps (FWHM)
Novel APD with negative feedback for free running
operationInternal resistor quenches rapidly
the avalancheSlow recharging-> nice results in free running
mode:poster of Tommaso Lunghi
Versatile detector moduleSpecifications: Gated mode up to 100 MHz Variable gate length 1ns to 10ns Free running
Integrated counters, clock, variable delay etc Inputs and outputs in NIM, ECL, TTL etc «cool» user interface Easy upgradable with new functions (TDC,
histogram)
id 210 as a whole
People: Jun Zhang (physicist), APD characterisation, measurements
Claudio Barreiro (engineer), pulser electronicsOliver Guinnard (engineer), design, electronics, mechanicsBernard Clausen (engineer), electronicsAlexis Rochas (physicist), concept and testingJean-Benoit Page (engineer), programming, user interfaceLaurent Monat (engineer), electronics and FPGATony Matteo (engineer), production
The Result:
Quantum Key Distribution
Quantum Cryptography is not a new coding method, it allows to create a secret key
Security is based on the laws of quantum physics “A measurement perturbs the system in an irreversible way”. A spy listening to the “quantum communication”, disturbs the system and will be detected.
The basic idea is simple
Alice EveBob
Error with 25 % probabilityÞ The error rate (QBER) indicates the
presence of Eve and the information she possesses(in practice typical QBER ~1-2%)
1
01
00
Key DistillationAlice Bob
Quantum channel
Public channel
(losses)
Qubits
TransmissionBasis
Reconciliation
QBERestimate
Error
correctionPrivacy
amplification
Sifted key
Raw key
Key Key
Smolin and BennettIBM 1989
id Quantique 20062 (dark) fibersDistance 100km
100 MHz EthernetNot One Time Pad!
The plug & play system is getting old
Faint laser BB 84, two way scheme5 MHz pulse rate1 kbit/s secret bit rate @ 25km
presented at CeBit 02 with guest star Sandra Pochon!
- Coherent faint laser pulses (µ~0.5)- 150 km of installed and standard fibres, 43dB of losses- SECOQC 2008 (Vienna)
Coherent-One-Way (COW) scheme
tB D B
D M 1D M 2
1 t BL ase r IM
b it 0b it 1 d ec o y
Industrial COW prototype: 1000 times higher bit rates
625 MHz rate (1.25 GHz pulse rate) 1 Mbit/s secret key rate @ 25km
WDM of quantum and classical channel real time distillation (FPGA) security, finite key analysis
The QCrypt Concept
100 Gb/s
1 Mb/s OTP
High-speed Quantum Key Distribution +
40 – 100Gbps enCRYPTion +
WDM
QKD Engine Results:
250 ps
Tfwhm=138 ps
500 600 700 800 900 10000.00
0.02
0.04
0.06
0.08
0.10
0.12
T=129 ps
Gate frequency: 1.25 GHz
Det
ectio
n ef
ficie
ncy
Delay [ps]
Intensity modulation Sinus gating detector
Short gatesLow afterpulsingHigh count rates
QKD and WDM Goal: Key distribution and high speed data
encryption over a single optical fibre Commercial QKD (plug & play)
and AES-encryptors (256 bits keys, 1 Gbps rate)
New Journal of Physics 12 (2010) 063027
Classical communication channel
Dedicated quantum channel
AliceBob AliceBob
Experimental Results
Fiber attenuation: -0.207 dB/kmDetection efficiency: 0.07Dark count rate: 510-6 ns-1
Dead time: 10 sDWDM isolation: 82 dB
Thank you for y
our
attentio
n