Quantum Information with Solid-State Devices VO 141.246 SS2012 - - PowerPoint PPT Presentation

Quantum Information with Solid-State Devices

VO 141.246 SS2012

• Dr. Johannes Majer

Lecture 6

tunnel junction

Shadow Evaporation

• 1. ele c tron b e a m w riting
• 2. d e v elop m e nt
• 3. first alu minu m e v a pora tion

e- e- e- e- e- e- PMM A/M A A Substra t e Al Al O 2 O 2

• 4. o xid a tion

Al Al

• 5. s e c ond alu minu m e v a pora tion
• 6. lift-off

PMM A PMM A PMM A

RF SET

LC tank circuit, impedance transformer

!1 !0.5 0.5 1 1.5 2 !1 !0.8 !0.6 !0.4 !0.2 0.2 0.4 0.6 0.8 1 x 10

!3

[1/2 | 0] [(!2!!1)/2 | 2Ec/e] [(!1!!2)/2 | !2Ec/e] Gate Charge ng=(Vg Cg)/e Source Drain Voltage (V)

!1 !0.5 0.5 1 1.5 2 !2 !1.5 !1 !0.5 0.5 1 1.5 2 x 10

!3

[!/Ec("2!"1)+1/2 | 4!/e] [(!/Ec+1/2)("2!"1) | 4!/e+2Ec/e] [!/Ec("1!"2)+1/2 | !4!/e] [(!/Ec+1/2)("1!"2) | !4!/e!2Ec/e] Gate Charge ng=(Vg Cg)/e Source Drain Voltage (V)

C2 C1 C2 C1

1 1 e e

Superconducting SET

Josephson quasi particle cycle

−1 −0.5 0.5 1 1.5 2 −2 −1.5 −1 −0.5 0.5 1 1.5 2 x 10

−3

[κ2(1/2+∆/Ec)−1| 2∆/e + Ec/e] [κ2(3/2+∆/Ec)−1 | 2∆/e + 3Ec/e] [−κ1(1/2+∆/Ec)+1 | 2∆/e + Ec/e] [−κ1(3/2+∆/Ec)+1 | 2∆/e + 3Ec/e] [κ2(1/2+∆/Ec)−1 | −2∆/e − Ec/e] [κ2(3/2+∆/Ec)−1 | −2∆/e − 3Ec/e] [−κ1(1/2+∆/Ec)+1 | −2∆/e − Ec/e] [−κ1(3/2+∆/Ec)+1 | −2∆/e − 3Ec/e] Gate Charge ng=(Vg Cg)/e

C2 C1 C2 C1

2 2 1 2e e

C2 C1

1 e

Superconducting RF-SET