In the sawyer system you obtain displacement D. In ferroelectrics with low conductivity is possible to consider D=P. 

Finally, if you integrate the signal the pure polarization is isolated.

Yes you can !

But take care because D-E loops recorded with S-T circuit may be subject to strong deformations hindering the ferroelectric polarization. You may be interested by our paper: "Numerical extraction of the true ferroelectric polarization..." in  Ferroelectrics, vol 274, p165-181 (2002).

Yes--Sawyer-Tower circuits were/are a major characterization method for ferroelectrics.  They provide researchers with individual control of parameters, unlike P-E analyzers.  Check Jaffe, Cook, & Jaffe or Lines & Glass, or Jona & Shrine in combination for Sawyer-Tower fundamentals and pay careful attention to parasitics.

Yes, Sawyer-Tower is one of the most traditional method used some ferroelectric properties, and there still are a some papers that make use of this method

Yes, but it might not be the true determination of intrinsic polarization. If your films are leaky than it hinders the  quantitative analysis of ferroelectric polarization.

You must confirm on which kind of samples (ceramics, single crysals or thin films) you wish to make the ferroelectric hysteresis measurements.

For thin films I could build a simple system using an oscilloscope and function generator.

So in order to suggest a good answer which would work out for you, it is important to know on what sample are planning to do the ferroelectric hsyteresis measurements.

What kind of ferroelectric materials (soft or hard) are you dealing with. Any idea whether they are low coercive or high coercive field.

Anyway when you build a system you do need a calibration sample, and satisfy yourself that you have been able to build a system, and are able to get reliable values. then you can verify on the same system by studying your research samples. 

 Accordingly the instrumentation requirements change. (from simple to sophisticated- costly to expensive.

If the above information is known then one easily suggest how to go about the measurements. So please let me know what kind of samples are you looking at.

Once I have this information I can suggest possible ways.

Prof. K. Sreenivas

To make it simple Sawer Tower circuit is basically a circuit which helps you to measure measure the P_E hysteresis loop of a ferroelectric materials. You can simple sinve wave (%0 Hz), and even triangular wave signals to measure the polarisation switching currents and hy loops. Classic measurements and original data on many ferroelectric materials in the history of ferroelectrics (like BaTiO3, and PZT) could be measured with the simple Sawer and Tower circuit.

You can find many papers in the journal of Review of SCientific instruments.

soon after the interest in ferroelectric thin films for non volatile memory devices, P-E analyzers- the commercial name of present day  equipment is being sold by some companies. They are  probaly computer driven. You can measure single shot hysteresis loop, and they apply different pulsed signals to extract the polarisation currents. But most of such equipment is pretty expensive.  It is not necessary that you need to have a PE analyzer to measure ferroelectric hysteresis loops.

As I said in my previous e-mail I simply used a function generator, sawer Tower circuit and an oscilloscope, and measured some of the best looking hy loops on PZT thin films.

K. Sreenivas