  We have demonstrated the electrical generation and detection of spin
polarization by the spin Hall effect (SHE) in platinum. The experiment was
performed in a non-local geometry without the use of ferromagnetic materials or
magnetic field. We designed a circuit that uses the SHE to convert a charge
current to a spin current, and the inverse SHE to convert the spin current back
into a charge signal. The experiments were carried out for temperatures from 10
K up to 290 K. We extracted the spin Hall conductivity and spin diffusion
length from the data with the aid of a spin diffusion model, and found the
values of 1.1 $\times 10^6$ $\Omega^{-1}$m$^{-1}$ and 80~nm, respectively, at
290 K. The spin Hall conductivity is two orders of magnitudes larger than the
previous record of $3.3\times10^4$ $\Omega^{-1}$m$^{-1}$. This observation may
have many potential applications in spintronics devices.
