novel approaches to optomechanical transduction
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Novel approaches to optomechanical transduction
Ondřej Černotík and Klemens HammererInstitut für Theoretische Physik, Leibniz Universität Hannover
DPG Frühjahrstagung Mainz, 10 March 2017
Ondrej Cernotík (Hannover): Novel approaches to optomechanical transductionˇˇ
Superconducting systems are among the best candidates for quantum computers.
2
R. Schoelkopf
Light is ideal for quantum communication owing to low losses and noise.
A. Zeilinger
Ondrej Cernotík (Hannover): Novel approaches to optomechanical transductionˇˇ
Mechanical oscillators can mediate coupling between microwaves and light.
3
R. Andrews et al., Nature Phys. 10, 321 (2014)
Ondrej Cernotík (Hannover): Novel approaches to optomechanical transductionˇˇ
Mechanical oscillators can mediate coupling between microwaves and light.
4
R. Andrews et al., Nature Phys. 10, 321 (2014)a1,out
a2,outa2,in
a1,in
a1
a2g2
g1b
H = g1(a†1b+ b†a1) + g2(a
†2b+ b†a2)
a(t) = Aa(t) +Bain
(t)
aout
(t) = Ca(t) +Dain
(t)
aout
(!) = S(!)ain
(!) = [D�C(A+ i!1)B]ain
(!)
Ondrej Cernotík (Hannover): Novel approaches to optomechanical transductionˇˇ
Mechanical oscillators can mediate coupling between microwaves and light.
5
R. Andrews et al., Nature Phys. 10, 321 (2014)a1,out
a2,outa2,in
a1,in
a1
a2g2
g1b
H = g1(a†1b+ b†a1) + g2(a
†2b+ b†a2)
g211
+g222
⌧ i
L. Tian, PRL 108, 153604 (2012)
Y.-D. Wang and A.A. Clerk, PRL 108, 153603 (2012)
g211
=g222
Impedance matching
i ⌧ !mResolved-sideband regime
Strong cooperativity Ci =4g2ii�n
� 1
Ondrej Cernotík (Hannover): Novel approaches to optomechanical transductionˇˇ 6
Better performance can be achieved by optimizing for a specific task.
-
O. Cernotík and K. Hammerer, PRA 94, 012340 (2016)ˇ
| 0i = (|0i+ |1i)(|0i+ |1i)
!
8<
:
|00i|11i
|01i+ |10i
/ h�1z + �2
zi
Ondrej Cernotík (Hannover): Novel approaches to optomechanical transductionˇˇ 7
We can also use new designs to improve efficiency and bandwidth.
z
H = g1(z)(a†1b+ b†a1) + g2(z)(a
†2b+ b†a2)
Ondrej Cernotík (Hannover): Novel approaches to optomechanical transductionˇˇ
g1
g2
8
Highly efficient transduction is possible using adiabatic state transfer.
L. Tian, PRL 108, 153604 (2012)Y.-D. Wang and A.A. Clerk, PRL 108, 153603 (2012)
z
H =q
g21(z) + g22(z)(d†1b+ b†d1)
d1 =1p
g21(z) + g22(z)[g1(z)a1 + g2(z)a2]
d2 =1p
g21(z) + g22(z)[g2(z)a1 � g1(z)a2]
Ondrej Cernotík (Hannover): Novel approaches to optomechanical transductionˇˇ 9
Transducer bandwidth can be increased by increasing the array size.
Ondrej Cernotík (Hannover): Novel approaches to optomechanical transductionˇˇ 10
Reflection from a large number of cavities introduces a phase shift.
Ondrej Cernotík (Hannover): Novel approaches to optomechanical transductionˇˇ 11
High conversion efficiency is possible in presence of losses and noise.
�n ⌧ gi4g2ii�n
� 14g2ii�n
� 1
i ⌧ !m i ⌧ !m i,! ⌧ !m
i ⌧ gi int ⌧ i
(int
⌧ i
prop
⌧ g2i
i
Temporal adiabatic
Single transducer
Transducer array
Mechanical noise
Counterrotating terms
Optical losses
Ondrej Cernotík (Hannover): Novel approaches to optomechanical transductionˇˇ 12
We must also limit backscattering.
RL
⌘ =L
R⌧ 1Needs
Ondrej Cernotík (Hannover): Novel approaches to optomechanical transductionˇˇ 13
Transducer array is an interesting platform for frequency conversion.
+ Large bandwidth
+ Multimode operation
- Needs an array
- Phase shift
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