SU1629975A1 - Gating current comparator - Google Patents

Abstract

The invention relates to a pulse technique and can be used to measure the characteristics of devices based on the Josephson effect for microwave electronics and computing. The purpose of the invention is to increase speed. The gated current comparator contains a Josephson contact 1, inductance element 2, resistor 3, input current bus gate 4, input signal bus 5, signal under study, output bus 6, and common bus 7. Using series-connected resistors 3 and inductance element 2 allows the set the gated current comparator to its initial state, which reduces the recovery time and, consequently, the response time. 3 kg.

Description

01 / 2.7

The invention relates to a pulse technique. And can be used to measure the characteristics of devices based on the Josephson effect for microwave electronics,

The purpose of the invention is to increase the speed by restoring the compacted 1 st comparator to its original state.

Figure 1 is a schematic diagram of a gated current comparator (SCT); figure 2 - threshold characteristic of the SCT; FIG. 3 is a timing diagram of input currents and output voltages,

The gated current comparator contains a Josephson contact 1, an inductance element 2, a resistor 3, an input bus 4 of the gate current pulses, an input bus 5 of the signal under study, an output bus 6 and a common bus 7, with the first output of the Joseph Son contact 1 connected to the common bus 7 , the second output is with the input bus 4 of the gate current pulses and the input plow 5 of the signal under study and the first output of the element 2 of the inductance, the second output of which is connected to the common bus 7 through the resistor 3.

The comparator works as follows.

The shape of the gate current pulse 1 is shown in FIG.

Measuring circuit produces. the current under investigation, which at the time of gating is compared with the threshold value Itfop (FIG. 2).

MTS performs the following sequence of actions. At the time of T., gates begin to form. current pulse I ,. If at the time T., when the strobe current pulse acquires the maximum value, the magnitude of the current is greater then a voltage Vg Vo appears on the bus B.

In the event of a voltage on the output bus 6 to the chain made up of the element 2 of the inductance and the resistor 3, the current begins to branch off, the value of which constantly increases. At time ТЈ, the voltage Vg becomes equal to zero, since the current flowing through the Josephson junction reaches an extremely small value at which it can still be in a state with a voltage. At this point, the gating cycle ends.

The gating cycle time is determined by the inductance L of the inductance element 2, the critical current IQ of the Josephson junction, the voltage of the slot Vo, on the josephonic junction. This time may be reduced to several tens of picoseconds. For the cycle time of gating, an approximate formula T takes place.

L 1L

CYCL4

- 2I0L / VA where

(R is the resistance of the resistor 3).

Claims (1)

Invention Formula A gated current comparator containing a Josephson junction, the first output of which is connected to the common bus, the second output connected to the output bus, the input bus of the current strobe pulses and the input bus of the signal under investigation, characterized in that, in order to increase speed, an inductance element and a resistor are introduced the first output of the inductance element is connected ъ by the second output of the Josephson contact, the second output of the inductance element is connected to the first output of the resistor, and the second output of the resistor is connected to General nm.  then FIG. 2 BUT Bj tj 3 five