I've been in this exact situation.
Did you write the paper on your own time (and outside an employee agreement that would give ownership of the paper to your employer)?
Or did you write it as the property of your employer?
It makes a difference because, in the latter case, it's not YOUR paper, it's your employer's, and they get the say on whether it is released and by who. You are still the author.
I make a point of making sure I maintain ownership of things I write for this very reason. I usually get it in the job negotiations before I commit to the job.
Will your new employer get value out of you presenting a paper at a conference? Will it help them sell consulting services? Will the conference help train you so your skills are even more valuable? If so, your new employer may be happy to pay for it.
In my case, I had a bad personal year my last year at the old employer. My wife had an operation, my daughter had an operation, my son went to prison (with the associated legal bills for us), both cars died and the refrigerator died. Needless to say, my funds were "tight".
My new employer was a consulting company so they were gung ho about me presenting the paper with their name and logo attached. The conference was a month after I switched jobs. I talked to them about it before joining them.
My credit cards were maxed and my ready cash had already been used up. This was pretty early in my paying career so I didn't have much in the way of an emergency fund saved up. My wife was in school and not working.
So, my employer arranged for a buddy of his, who would be at the conference, to pay for my hotel. He was also a travel agent and was able to get a really good rate, but he had to personally check in. I was a bit nervous about it because two unrelated guys would be checking into this one bed hotel room. Only I would be staying in the room, but how would that play out in the hotel check in process.
He was a bit nervous about it to. We were standing in line at the hotel and both of us, in the same moment, realized, "Hey! This is San Francisco! No one will care!"
