Quantum cost (QC) refers to the cost of the circuit in terms of the cost of a

primitive gate. It is calculated knowing the number of primitive reversible logic gates (1*1 or 2*2) required to realize the circuit

Quantum cost of FG, TG, FRG, PG and BVFgates are 1, 5, 5, 4 and, 2 respectively.

The quantum cost of 1x1 reversible gates is zero, and quantum cost of 2x2 reversible gates is one.

Thanks for your response sir.. even i got that from my  paper..but how they are telling for FG 1,TG 5 ,PG 2....etc..

Hello Nireesha

you have to look at quantum diagram of Toffoli gate/Feynman gate/Peres gate. you will get to see primary gates like v,v+,CNOT gates. count the number of primary gates which will give u the cost, since cost of primary gates is equal to 1, count itself is quantum cost of that gate.

Regards

Jayashree

NOT gate cost is 1 not zero, pls refer the link http://webhome.cs.uvic.ca/~dmaslov/definitions.html

Hai Jayashree

please see the 2nd paragraph of 2nd page of the below paper

http://www.ijareeie.com/upload/2013/august/28_DESIGN.pdf

This link is useful for the calculation of the QC

http://www.hri.res.in/~iwqi12/iwqi12_talks/Poster_anindita_banerjee.pdf

I have this doc. Anyways am still not ready to agree with NOT gate cost. I have written mail to concerned person, if I get the reply will post here.

sure. Even I also feel that I am wrong. I will go through the more documents and will get back to you

Hai

   I went through more papers and QC of NOT gate is 1 only. sorry for my misleading comments.

Using Revkit tool, you can calculate quantum cost

Then what gate has the quantum cost as Zero??

Possible in both Revkit and RCviewer+ tool. In Revkit truth table to quantum circuit possible and in case of RCviewer optimization of quantum circuit is possible. That additional feature is possible in RCviewer but code written in ..tfc format.

I agree NOT gate has 1 QC, because code this code written in RCviewer gives a 1 QC. The code is

v a

.i a

.o a

BEGIN

t1 a

END

@Neeraj Mishra

Sir can you please help me to write the code of  HNFG gate in .tfc format,,,

I assume the last gate was swap gate which is uncontrolled fredkin 2-bit gate. The tfc format is as follows: 

.v a,b,c,d

.i a,b,c,d

.o a,b,c,d

BEGIN

t2 a,c

t2 b,d

f2 b,c

END

 @Mustapha Yusuf Abubakar 

the code above written shows the Q cost of 5, but the paper in which it is proposed it is showing only 2,,,,,,NOW WHAT VALUE SHOULD I TAKE....

The paper is attached...find the circuit at page 2

According to authors, there is no swap gate, they are hardwired in such a way to Cris Cross outputs. So qcost is equal to 2.

According to authors, there is no swap gate, they are hardwired in such a way to Cris Cross outputs. So qcost is equal to 2.

That is why i said, i assumed the last twist is a swap gate. Since in the paper it is only two Feynman gates (CNOT), just remove  (f2 b,c) in the tfc file and the quantum cost would be 2 as Jayashree hv mentioned. 

thanku all....

So, if a propose a new gate in which there is cris cross of outputs at the end in order to achieve reversibility, i need not to consider that amount of cost.

@Jayashree hv

Can you please attach the reference of authors where the above statement can be cited.....(According to authors, there is no swap gate, they are hardwired in such a way to Cris Cross outputs)...

That will be your most kindness,,,

I meant the authors of the paper which  you had referred and attached in your query

I meant the authors of the paper which  you had referred and attached in your query

Thank you Jayashree hv

How to relate the quantum cost of a reversible circuit ( say 8x8 multiplier) to that of the power dissipated by the equivalent CMOS circuit? How do we quantify the energy saved in respect of the circuit built using RGs?

Sir, I can’t understand the quantum representation of these attached gates. Can you please help me how the quantum representation (how to draw) and minimum quantum cost of these two gates?

Quantum cost is basically number of primitive reversible gates such as C-NOT, V-gate, V+ , and NOT gate ( both 2x2 as well as 1x1 ) utilized in constructing a quantum circuit.

What is the quantum cost of TNOR gate For 2×2 and 3×3 ?

Quantum cost is counting the number of primitives gate in the quantum circuit. But certain condition must be met to evaluate the quantum cost like design must be reversible, equal input and output, no feedback path, and loops.

you must to find its quantum implementation to know how much it has of 1*1 and 2*2 gates.