How can I include small line before or above title in 2 columns document in center?

I’m working on an expose (research proposal) and I selected this template in overleaf which is 2 columns. now the problem is I want to include a short line with the small size above title in the center of 2 columns document. I tried this answer unsuccessfully.
So far based on the designed document class in the template I could display using title itself by as follows:

documentclass[%
 reprint,
%superscriptaddress,
%groupedaddress,
%unsortedaddress,
%runinaddress,
%frontmatterverbose, 
%preprint,
%preprintnumbers,
%nofootinbib,
%nobibnotes,
%bibnotes,
 amsmath,amssymb,
 aps,
%pra,
%prb,
%rmp,
%prstab,
%prstper,
%floatfix,
]{revtex4-2}

usepackage{graphicx}% Include figure files
usepackage{dcolumn}% Align table columns on decimal point
usepackage{bm}% bold math
usepackage{hyperref}% enables hyperlinks in the PDF
usepackage{wrapfig}
usepackage{lipsum}

begin{document}

title{small Exposé für Geschäftsidee  LARGE Proposal Title}% Force line breaks with 

bibliography{bibfile}% Produces the bibliography via BibTeX.

end{document}

The problem of the currently used method is the title occupies at least 2 lines.
So far the output is as follows:

I was wondering if there is an elegant way to display it without using title itself. Any helps will be appreciated.