A cavity-enhanced waveguide quantum memory

Hassan Mallahzadeh , Daniel Oblak, Neil Sinclair, Wolfgang Tittel

Canadian Association of Physicists congress, Sudbury, Ontario

June 19, 2014

|𝜓 1 ⟩ |𝜓 2 ⟩ |𝜓 3 ⟩ |𝜓 4 ⟩ |𝜓 5 ⟩ |𝜓 6 ⟩ |𝜓 7 ⟩ |𝜓 8 ⟩

The quest for an efficient optical quantum memory

|𝜓 1 ⟩ |𝜓 4 ⟩ |𝜓 5 ⟩ |𝜓 8 ⟩

|𝜓 ⟩ Quantum Memory |𝜓 ⟩

Nature Photonics 3, 706 - 714 (2009)

Frequency Comb memoryThe Mathematical Background

Fourier transform

Δt=Δν

Fourier transform

FrequencyTime

Frequency Comb memoryThe Physical Limitations

• Limited absorption pick height • Finite absorption pick width• Kramers-Kronig Relations

The cavity enhanced frequency comb memory

Memory

Front mirrorT=Round trip absorption Back mirror

R=100%.

f

dinput

output

Phys. Rev. A 82, 022310 (2010)Phys. Rev. Lett. 110, 133604 (2013)

The Atomic Frequency Comb (AFC) in rare earth ion doped crystals

• Very narrow homogenous line width (0.1-100KHz) at cryogenic temperatures(~<4k).,

Ti:Tm:LiNbO3

Phys. Rev. A 79, 052329 (2009)

The experiment’s layout

BS

Detector

Laser AOM PM

CryostatT<1k

Ti:Tm:LiNbO3

R=1

𝑅=(1.5−11.5+1 )2

=0.04

𝑅=( 2.2−12.2+1 )2

=0.14

Hole burning results

10 GHz

10 GHz

Have to be done:

• Make an AFC inside the cavity by hole burning on equal intervals

• Minimize the reflected light• Perform the experiment at single photon level

10

Thank You!

Backup slide

Fiber Crystal

R1=4%

R2=14%

R3=100%