TY - JOUR
T1 - High performance DC superconducting quantum interference device utilizing a bicrystal junction with a 30° misorientation angle
AU - Minotani, Tadashi
AU - Kawakami, Satoru
AU - Kiss, Takanobu
AU - Kuroki, Yukinori
AU - Enpuku, Keiji
PY - 1997/8/15
Y1 - 1997/8/15
N2 - A high Tc dc superconducting quantum interference device (SQUID) was fabricated using a bicrystal junction with a misorientation angle of θ = 30°. The junction with a width of 2 μm exhibited high resistance Rs = 10Ω and critical current I0 = 25 μA at T = 77 K. This gives a I0Rs as high as 250 μV. These values indicate that the bicrystal junction has great potential for the development of high performance SQUIDs. The SQUID fabricated with a 30° junction exhibited voltage modulation depths as high as ΔV = 85 μV, 40 μV and 20 μV at T = 77 K for the inductance values of Ls = 60 pH, 100 pH and 160 pH, respectively. These are the highest values reported so far. Preliminary noise measurement showed that the flux noise of the SQUID is less than 8 μΦ0/Hz1/2 for the white noise region, and less than 70 μΦ0/Hz1/2 at f = 1 Hz when the 60 pH-SQUID is dc biased and operated with a conventional Flux Locked Loop (FLL) circuit.
AB - A high Tc dc superconducting quantum interference device (SQUID) was fabricated using a bicrystal junction with a misorientation angle of θ = 30°. The junction with a width of 2 μm exhibited high resistance Rs = 10Ω and critical current I0 = 25 μA at T = 77 K. This gives a I0Rs as high as 250 μV. These values indicate that the bicrystal junction has great potential for the development of high performance SQUIDs. The SQUID fabricated with a 30° junction exhibited voltage modulation depths as high as ΔV = 85 μV, 40 μV and 20 μV at T = 77 K for the inductance values of Ls = 60 pH, 100 pH and 160 pH, respectively. These are the highest values reported so far. Preliminary noise measurement showed that the flux noise of the SQUID is less than 8 μΦ0/Hz1/2 for the white noise region, and less than 70 μΦ0/Hz1/2 at f = 1 Hz when the 60 pH-SQUID is dc biased and operated with a conventional Flux Locked Loop (FLL) circuit.
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U2 - 10.1143/jjap.36.l1092
DO - 10.1143/jjap.36.l1092
M3 - Article
AN - SCOPUS:0031207296
VL - 36
SP - L1092-L1095
JO - Japanese Journal of Applied Physics, Part 2: Letters
JF - Japanese Journal of Applied Physics, Part 2: Letters
SN - 0021-4922
IS - 8 SUPPL. B
ER -